LMLechko

Chapter 29, part 2
Development and Inheritance
SECTION 29-5 The Second and Third Trimesters
Second and Third Trimesters
Second trimester
Organ systems increase in complexity
Third trimester
Many organ systems become fully functional
Fetus undergoes largest weight change
At end of gestation fetus and uterus push maternal organs out of position
Figure 29.9 The Second and Third Trimesters
Figure 29.10 Growth of the Uterus and Fetus
Figure 29.10 Growth of the Uterus and Fetus
Developing fetus totally dependent on maternal organs
Maternal adaptations include increased
Respiratory rate
Tidal volume
Blood volume
Nutrient and vitamin uptake
Glomerular filtration rate
Structural and Functional Changes in the Uterus
Progesterone inhibits uterine muscle contraction
Opposed by estrogens, oxytocin and prostaglandins
Multiple factors interact to produce labor contractions in uterine wall
Figure 29.11 Factors Involved in the Initiation of Labor and Delivery
SECTION 29-6 Labor and Delivery
Goal of labor is parturition
Stages of labor
Dilation
The cervix dilates and fetus moves toward cervical canal
Expulsion
The cervix completes dilation and fetus emerges
Placental
Ejection of the placenta
Figure 29.12 The Stages of Labor
Other labor and delivery situations
Premature labor
True labor begins before fetus has completed normal development
Difficult deliveries
When the fetus faces the pubis rather than the sacrum
The legs or buttocks enter the vaginal canal first (breech births)
Multiple births
Twins, triplets, etc.
Dizygotic or monozygotic situations
SECTION 29-7 Postnatal Development
Postnatal life stages
Neonatal period
Infancy
Childhood
Adolescence
Maturity
Senescence begins at maturity and ends in death
The neonatal period
From birth to one month
Respiratory, circulatory, digestive and urinary systems adjust
Infant must thermoregulate
Maternal mammary glands secrete colostrum first few days
Milk production thereafter
Both secretions are released via the milk let-down reflex
Body proportions change during infancy and childhood
Figure 29.13 The Milk Let-Down Reflex
Figure 29.14 Growth and Changes in Body Form
Adolescence
Begins at puberty
The period of sexual maturation
Ends when growth is completed
Puberty marked by
Increased production of GnRH
Rapid increase in circulating FSH and LH
Ovaries and testes become sensitive to FSH / LH
Gamete production initiated
Sex hormones produced
Growth rate increases
Hormonal changes at puberty produce gender specific differences in system
Differences are retained throughout life
Adolescence continues until growth completed
Further changes occur when sex hormones decline
Menopause
Male climacteric
Senescence
Aging affects functional capabilities of all system
SECTION 29-8 Genetics, Development, and Inheritance
Genes and chromosomes
Every somatic cell carries copies of the 46 original chromosomes in the zygote
Genotype – Chromosomes and their component genes
Phenotype – physical expression of the genotype
Patterns of inheritance
Somatic cells contain 23 pairs of chromosomes
Homologous chromosomes
22 pair of autosomes and one pair of sex chromosomes
Chromosomes contain DNA
Genes are functional segments of DNA
Figure 29.15 Human Chromosomes
Various forms of a gene are called alleles
Homozygous if homologous chromosomes carry the same alleles
Heterozygous if homologous chromosomes carry different alleles
Alleles are either dominant or recessive depending on expression
Punnett square diagram predicts characteristics of offspring
Figure 29.16 Predicting Phenotypic Characteristics by Using Punnett Squares
Inheritance
Simple inheritance
Phenotypic characteristics are determined by interactions between single pair of alleles
Polygenic inheritance
Phenotypic characteristics are determined by interactions among alleles on several genes
Sources of individual variation
Genetic recombination
Gene reshuffling
Crossing over and translocation
Occurs during meiosis
Spontaneous mutations
Random errors in DNA replication
Figure 29.17 Crossing over and Translocation
Sex-linked inheritance
Sex chromosomes are X chromosome and Y chromosome
Male = XY
Female = XX
X chromosome carries X-linked (sex linked) genes
Affect somatic structures
Have no corresponding alleles on Y chromosome
Figure 29.18 X-Linked inheritance
The Human Genome Project
Mapped more than 38,000 of our genes
Including some responsible for inherited disorders
Figure 29.19 A Map of the Human Chromosomes
You should now be familiar with:
The relationship between differentiation and development, and the various stages of development
The process of fertilization
The three prenatal periods and describe the major events associated with each
The importance of the placenta as an endocrine organ
You should now be familiar with:
The structural and functional changes in the uterus during gestation
The events that occur during labor and delivery
The basic principles of genetics as they relate to the inheritance of human traits

Chapter 29, part 1
Development and Inheritance
Learning Objectives
Explain the relationship between differentiation and development and specify the various stages of development
Describe the process of fertilization
List the three prenatal periods and describe the major events associated with each
Discuss the importance of the placenta as an endocrine organ
Learning Objectives
Discuss the structural and functional changes in the uterus during gestation
List and discuss the events that occur during labor and delivery
Relate basic principles of genetics to the inheritance of human traits
SECTION 29-1 An Overview of Topics in Development
Differentiation and development
Development
Gradual modification of physical and physiological characteristics
Differentiation
The creation of different types of cells
Stages of development
Prenatal development
Embryological
Changes occurring the first two months after fertilization
Fetal
Begins at the start of the ninth week and continues until birth
Postnatal development
Commences at birth and continues to maturity
SECTION 29-2 Fertilization
Fertilization (conception)
Occurs in the uterine tubes
Within a day of ovulation
Spermatozoa cannot fertilize an ovum until after capacitation
Figure 29.1 Fertilization
Figure 29.1 Fertilization
The Oocyte at Ovulation
Oocyte is in meiosis II
Surrounded by the corona radiate
Spermatozoa release hyaluronidase and acrosin
Enzymes required to penetrate corona radiate
Single spermatozoan contacts oocyte, fertilization begins
Oocyte activation
Oocyte activation
Oocyte completes meiosis II
Functionally mature ovum
Female pronucleus and male pronucleus fuse (amphimixis)
Polyspermy prevented by membrane depolarization and cortical reaction
SECTION 29-3 The Stages of Prenatal Development
Embryonic and Fetal Periods
Induction
During prenatal development differences in cytoplasmic composition trigger changes in genetic activity
Gestation periods
Three trimesters
SECTION 29-4 The First Trimester
The First Trimester
Cleavage
Zygote becomes a preembryo then a blastocyst
Implantation
Blastocyst burrows into uterine endometrium
Placentation
Blood vessels form around blastocyst and placenta develops
Embryogenesis
Formation of a viable embryo
Cleavage and blastocyst formation
A series of cell divisions that subdivides the cytoplasm of the zygote
Trophoblast – outer layer of cells
Inner cell mass – cluster of cells at one end of blastocyst
Figure 29.2 Cleavage and Blastocyst Formation
Implantation
Occurs about 7 days after fertilization
Trophoblast enlarges and spreads
Maternal blood flows through open lacunae
Gastrulation
Embryonic disc composed of germ layers
Endoderm
Mesoderm
Ectoderm
Figure 29.3 Stages in Implantation
Figure 29.4 The Inner Cell Mass and Gastrulation
Germ layers
Gastrulation
By day 12 surface cells move toward the primitive streak
A third germ layer forms
The three germ layers are:
Ectoderm – superficial cells that did not migrate
Endoderm – cells facing the blastocoele
Mesoderm – migrating cells between ectoderm and endoderm
Extraembryonic Membranes
Four extraembryonic membranes:
Yolk sac
Amnion
Allantois
Chorion
Figure 29.5 Extraembryonic Membranes and Placenta Formation
Figure 29.5 Extraembryonic Membranes and Placenta Formation
Figure 29.5 Extraembryonic Membranes and Placenta Formation
Embryo Anatomy
Yolk sac
Important site of blood cell formation
Amnion
Encloses fluid that surrounds and cushions developing embryo
Allantois
Eventually becomes bladder
Chorion
Figure 29.6 A Three-Dimensional View of Placental Structure
Placentation
Chorionic villi extend into maternal tissue
Forms intricate branching network for maternal blood
Umbilical cord connects fetus to placenta
Hormones of the placenta
Trophoblast secretes hormones to maintain pregnancy
HCG
Estrogens
Progesterone
hPL
Placental prolactin
relaxin

Are you aware that there is really only one meeting session to go over all thwe material?
I do not believe that we can do that. Especially with the genetic cross problems and developmental models. Really need to have the lab final on the day of the lecture fianl. It really will not make a difference. Material is the same, it would still be like studying once. You just have an extra week to accomplish the task!


sincerely,

Mr. Lechko


send e-mail; canucmelml@hotmail.com

Chapter 28, part 4
The Reproductive System
Uterine cycle
Repeating series of changes in the endometrium
Continues from menarche to menopause
Menses
Degeneration of the endometrium
Menstruation
Proliferative phase
Restoration of the endometrium
Secretory phase
Endometrial glands enlarge and accelerate their rates of secretion
Figure 28.20 The Uterine Cycle
The vagina
Major functions
Passageway for elimination of menstrual fluids
Receives the penis during sexual intercourse
Forms the inferior portion of the birth canal
Figure 28.21 The Histology of the Vagina
External genitalia
Vulva
Vestibule
Labia minora and majora
Paraurethral glands
Clitoris
Lesser and greater vestibular glands
Figure 28.22 The Female External Genitalia
Mammary glands
Pectoral fat pad
Nipple surrounded by the areola
Function in lactation under control of reproductive hormones
Figure 28.23 The Mammary Glands
Hormones of the female reproductive cycle
Control the reproductive cycle
Coordinate the ovarian and uterine cycles
Hormones of the female reproductive cycle
Key hormones include:
FSH
Stimulates follicular development
LH
Maintains structure and secretory function of corpus luteum
Estrogens
Have multiple functions
Progesterones
Stimulate endometrial growth and secretion
Figure 28.25 The Hormonal Regulation of Ovarian Activity
Figure 28.26 The Hormonal Regulation of the Female Reproductive Cycle
Figure 28.26 The Hormonal Regulation of the Female Reproductive Cycle
SECTION 28-4 The Physiology of Sexual Intercourse
Male sexual function
Arousal
Leads to erection of the penis
Parasympathetic outflow over the pelvic nerves
Emission and ejaculation
Occur under sympathetic stimulation
Results in semen being pushed toward external urethral opening
Detumescence
Subsidence of erection
Mediated by the sympathetic nervous system
Female sexual function
Stages are comparable to those of male sexual function
Arousal causes clitoral erection
Vaginal surfaces are moistened
Parasympathetic stimulation causes engorgement of blood vessels in the nipples
SECTION 28-5 Aging and the Reproductive System
Menopause
The time that ovulation and menstruation cease
Typically around age 45-55
Accompanied by a decline in circulating estrogen and progesterone
Rise in GnRH, FSH, LH
Male climacteric
Levels of circulating testosterone begin to decline
FSH and LH levels rise
Gradual reduction in sexual activity
You should now be familiar with:
The components of the reproductive system, and their functions
The components of the male and female reproductive systems
The processes of meiosis and gametogenesis in both sexes
You should now be familiar with:
The roles played by the male reproductive tract and accessory glands in the functional maturation, nourishment, storage, and transport of spermatozoa
The anatomical, physiological, and hormonal aspects of the male and female reproductive cycles
The physiology of sexual intercourse

Chapter 28, part 3
The Reproductive System
SECTION 28-3 The Reproductive System of the Female
Principle organs of the female reproductive system
Ovaries
Uterine tubes
Uterus
Vagina
Support and stabilization
Ovaries, uterine tubes and uterus enclosed within broad ligament
Mesovarium supports and stabilizes ovary
Figure 28.13 The Female Reproductive System
The ovaries
Held in position by ovarian and suspensory ligaments
Blood vessels enter at ovarian hilus
Tunica albuginea covers ovary
Figure 28.14 The Ovaries and Their Relationships to the Uterine Tube and Uterus
Oogenesis
Ovum production
Occurs monthly in ovarian follicles
Part of ovarian cycle
Follicular phase (preovulatory)
Luteal phase (postovulatory)
Figure 28.15 Oogenesis
The ovarian cycle
Steps in the ovarian cycle
Formation of primary, secondary, and tertiary follicles
Ovulation
Formation and degeneration of the corpus luteum
Degradation of the corpus luteum
Figure 28.16 The Ovarian Cycle
Figure 28.16 The Ovarian Cycle
The Uterine tubes
Uterine tubes (Fallopian tubes or oviducts)
Infundibulum
End closest to the ovary with numerous fimbriae
Ampulla
The middle portion
Isthmus
A short segment connected to the uterine wall
Each uterine tube opens directly into uterine cavity
Fertilization occurs in uterine tube
12-24 hours after ovulation
During passage from infundibulum to uterus
Figure 28.17 The Uterine Tubes
The uterus
Muscular organ
Mechanical protection
Nutritional support
Waste removal for the developing embryo and fetus
Supported by the broad ligament and 3 pairs of suspensory ligaments
Uterus
Major anatomical landmarks
Body
Isthmus
Cervix
Cervical os (internal orifice)
Uterine cavity
Cervical canal
Internal os (internal orifice)
Uterine wall consists of three layers:
Myometrium – outer muscular layer
Endometrium – a thin, inner, glandular mucosa
Perimetrium – an incomplete serosa continuous with the peritoneum
Figure 28.18 The Uterus
Figure 28.18 The Uterus
Figure 28.19 The Uterine Wall
Figure 28.19 The Uterine Wall

Chapter 28, part 2
The Reproductive System
Spermatogenesis
Seminiferous tubules
Contain spermatogonia
Stem cells involved in spermatogenesis
Contain sustentacular cells
Sustain and promote development of sperm
Figure 28.5 The Seminiferous Tubules
Figure 28.5 The Seminiferous Tubules
Figure 28.6 Chromosomes in Mitosis and Meiosis
Spermatogenesis
Spermatogenesis involves three processes
Mitosis
Meiosis
Spermiogenesis
Figure 28.7 Spermatogenesis
Anatomy of spermatozoon
Each spermatozoon has:
Head
Nucleus and densely packed chromosomes
Middle piece
Mitochondria that produce the ATP needed to move the tail
Tail
The only flagellum in the human body
Figure 28.8 Spermiogenesis and Spermatozoon Structure
Male reproductive tract
Testes produce mature spermatozoa
Sperm enter epididymus
Elongated tubule with head, body and tail regions
Monitors and adjusts fluid in seminiferous tubules
Stores and protects spermatozoa
Facilitates functional maturation of spermatozoa
Figure 28.9 The Epididymus
Ductus deferens AKA vas deferens
Begins at epididymus
Passes through inguinal canal
Enlarges to form ampulla
Ejaculatory duct at base of seminal vesicle and ampulla
Empties into urethra
Urethra
Urinary bladder to tip of penis
Three regions
Prostatic
Membranous
Penile
Accessory glands
Seminal vesicles
Active secretory gland
Contributes ~60% total volume of semen
Secretions contain fructose, prostaglandins, fibrinogen
Accessory glands
Prostate gland
Secretes slightly acidic prostate fluid
Bulbourethral glands
Secrete alkaline mucus with lubricating properties
Figure 28.10 The Ductus Deferens and Accessory Glands
Contents of Semen
Typical ejaculate = 2-5 ml fluid
Contains between 20 – 100 million spermatozoa per ml
Seminal fluid
A distinct ionic and nutritive glandular secretion
External genitalia
Male external genitalia consist of the scrotum and the penis
Skin overlying penis resembles scrotum
Penis
Contains three masses of erectile tissue
2 corpora cavernosa beneath fascia
1 corpus spongiosum surrounding urethra
Dilation of erectile tissue produces erection
Figure 28.11 The Penis
Hormones and male reproductive function
FSH (Follicle stimulating hormone)
Targets sustentacular cells to promote spermatogenesis
LH (leutinizing hormone)
Causes secretion of testosterone and other androgens
GnRH (Gonadotropin releasing hormone)
Testosterone
Most important androgen
Figure 28.12 Hormonal Feedback and the Regulation of the Male Reproductive Function

Chapter 28, part 1
The Reproductive System
SECTION 28-1 The Reproductive System
Learning Objectives
Specify the components of the reproductive system, and summarize their functions
Describe the components of the male and female reproductive systems
Outline the processes of meiosis and gametogenesis in both sexes
Explain the roles played by the male reproductive tract and accessory glands in the functional maturation, nourishment, storage, and transport of spermatozoa
Learning Objectives
Summarize the anatomical, physiological, and hormonal aspects of the male and female reproductive cycles
Discuss the physiology of sexual intercourse
Reproductive System
Reproductive system functions in gamete
Production
Storage
Nourishment
Transport
Fertilization
Fusion of male and female gametes to form a zygote
SECTION 28-1 Introduction to the Reproductive System
Reproductive system includes:
Gonads (testes, ovaries)
Ducts
Accessory glands and organs
External genitalia
Males and Females
Males
Testes produce spermatozoa
Expelled from body in semen during ejaculation
Females
Ovaries produce oocytes
Immature ovum
Travels along uterine tube toward uterus
Vagina connects uterus with exterior of body
SECTION 28-2 The Reproductive System of the Male
Male Reproductive System
Pathway of spermatozoa
Epididymis
Ductus deferens
Ejaculatory duct
Accessory organs
Seminal vesicles
Prostate gland
Bulbourethral glands
Scrotal sac encloses testes
Penis
Figure 28.1 The Male Reproductive System
The testes
Descent of the testes
Movement of testes through inguinal canal into scrotum
Occurs during fetal development
Testes remain connected to internal structures
Spermatic cords
Figure 28.2 The Descent of the Testes
Figure 28.2 The Descent of the Testes
Figure 28.3 The Male Reproductive System in Anterior View
Male Anatomy
Musculature of scrotal sac
Dartos muscle wrinkles scrotal sac
Cremaster muscle pulls sac close to body
Testes anatomy
Tunica albuginea surrounds testis
Septa extend from tunica albuginea to epididymus
Lobules
Sperm production
In seminiferous tubules
Interstitial cells between seminiferous tubules
Secrete sex hormones
Sperm pass through rete testis
Efferent ductules connect rete testis to epididymus
Figure 28.4 The Structure of the Testes

SECTION 22-6 B Cells and Antibody-mediated Immunity
B cell sensitization of activation
Sensitization – the binding of antigens to the B cell membrane antibodies
Antigens then displayed on B cell Class II MHC
TH cells activated by same antigen stimulate B cell
Active B cell differentiates into Memory B Cell or Plasma cell
Plasma cells synthesize and release antibody
Figure 22.20 The Sensitization and Activation of B Cells
Antibodies structure
Antibodies are Y-shaped proteins consisting of:
Two parallel polypeptide chains
Heavy chains and light chains
Constant region and variable region
Antigen binding site
Figure 22.21 Antibody Structure
Figure 22.21 Antibody Structure
Figure 22.21 Antibody Structure
Actions of antibodies include:
Neutralization
Agglutination and precipitation
Activation of complement
Attraction of phagocytes
Opsinization
Stimulation of inflammation
Prevention of adhesion
Classes of Antibodies (immunoglobins)
IgG – resistance against many viruses, bacteria and bacterial toxins
IgE – accelerates local inflammation
IgD – found on the surface of B cells
IgM – first type secreted after antigen arrives
IgA – primarily found in glandular sec
Primary and secondary antibody response
Primary response
Takes about two weeks to develop
The Lymphatic System and Immunity
Produced by plasma cells
Secondary response
Rapid increase in IgG
Maximum antibody titer app
Figure 22.22 The Primary and Secondary Immune Responses
Figure 22.23 An Integrated Summary of the Immune Response
Figure 22.25 The Course of the Body’s Response to Bacterial Infection
Focus on Hormones of the Immune System
Interleukins
Increase T cell sensitivity
Stimulate B cell activity, plasma formation, and antibody production
Enhance nonspecific defenses
Moderate the immune system
Interferons
Tumor Necrosis Factors (TNFs) slow tumor growth
Colony Stimulating Factors (CSFs)
SECTION 22-7 Normal and Abnormal Resistance
Development of the Immune Response
Immunological competence
The ability to demonstrate an immune response after exposure to an antigen
Fetuses receive immunity from the maternal bloodstream
Infants acquire immunity following exposure
Immune disorders
Autoimmune disorders
Immune response mistakenly targets normal cells
Immunodeficiency diseases
Immune system does not develop properly or is blocked
Allergies
Inappropriate or excessive immune response to allergens
Immediate hypersensitivity (type I)
Cytotoxic reactions (type II)
Immune complex disorders (type III)
Delayed hypersensitivity (type IV)
Anaphylaxis
Circulating allergen affects mast cells throughout body
Figure 22.26 The Mechanism of Anaphylaxis
Stress and the immune response
Interleukin-1 released by active macrophages
Triggers release of ACTH resulting in glucocorticoid release
Moderates the immune response
Lowers resistance to disease
Stress can cause the following:
Depression of the inflammatory response
Phagocytic reduction
Inhibition of interleukin secretion
SECTION 22-8 Aging and the Immune Response
With age
Immune system becomes less effective
Increased susceptibility to infection
Immune surveillance declines
You should now be familiar with:
The structure and function of lymphatic cells, tissues and organs
The body’s nonspecific defenses and the components and mechanisms of each
Specific resistance, cell-mediated immunity and antibody mediated immunity
The role of the T cell, B cell and antibodies in specific immunity
The origin, development, activation and regulation of normal resistance to disease
The effects of stress and aging on the immune system

Chapter 22, part 3
The Lymphatic System and Immunity
SECTION 22-4 Specific Defenses
Forms of immunity
Innate immunity
Genetically determined
Present at birth
Acquired immunity
Not present at birth
Achieved by exposure to antigen
Active immunity
Passive immunity
Figure 22.14 Types of Immunity
Properties of immunity
Specificity – activated by and responds to a specific antigen
Versatility – is ready to confront any antigen at any time
Memory – "remembers" any antigen it has encountered
Tolerance – responds to foreign substances but ignores normal tissues
The immune system response
Antigen triggers an immune response
Activates T cells and B cells
T cells are activated after phagocytes exposed to antigen
T cells attack the antigen and stimulate B cells
Activated B cells mature and produce antibody
Antibody attacks antigen
Figure 22.15 An Overview of the Immune Response
SECTION 22-5 T cells and Cell-mediated Immunity
Major types of T cells
Cytotoxic T cells (TC) – attack foreign cells
Helper T cells (TH) – activate other T cells and B cells
Suppressor T cells (TS) – inhibit the activation of T and B cells
Antigen presentation
Antigen-glycoprotein combination appears on a cell membrane
Called MHC proteins (Major Histocompatibility Complex)
Coded for by genes of the MHC
T-cells sensitive to the antigen are activated upon contact
MHC classes
Class I – found on all nucleated cells
Class II – found on antigen presenting cells and lymphocytes
Lymphocytes respond to antigens bound to either class I or class II MHC proteins
Antigen recognition
T cell membranes contain CD markers
CD3 markers present on all T cells
CD8 markers on cytotoxic and suppressor T cells
CD4 markers on helper T cells
Figure 22.16 Antigens and MHC Proteins
Figure 22.16 Antigens and MHC Proteins
Figure 22.16 Antigens and MHC Proteins
Activation of CD8 cells
Responds quickly giving rise to other T cells
Cytotoxic T cells – seek out and destroy abnormal cells
lymphotoxin
Memory TC cells – function during a second exposure to antigen
Suppressor T cells – suppress the immune response
Figure 22.17 Antigen Recognition and the Activation of Cytotoxic T Cells
Figure 22.17 Antigen Recognition and the Activation of Cytotoxic T Cells
Activation of CD4 T cells by antigens presented on class II MHC proteins
Produces helper T cells and memory T cells
Activated helper T cells
Secrete lymphokines that coordinate specific and nonspecific defenses
Enhance nonspecific defenses
Stimulate the activity of NK cells
Promote activation of B cells
Figure 22.18 Antigen Recognition and Activation of Helper T cells
Figure 22.19 A Summary of the Pathways of T Cell Activation

Chapter 22, part 2
The Lymphatic System and Immunity
The Thymus
Located behind sternum in anterior mediastinum
Capsule
Two lobes
Divided into lobules, each with a cortex and medulla
Cortical lymphocytes surrounded by reticular endothelial cells
Maintain blood–thymus barrier
Secretes thymic hormones: thymosins, thymopoietins, and thymulin
Figure 22.8 The Thymus
The Spleen
Largest mass of lymphoid tissue
Cellular components form pulp
Red pulp contains RBC
White pulp similar to lymphoid nodules
Spleen functions include
Removal of abnormal blood cells and other blood components
Storage of iron
Initiation of the specific immune response
Figure 22.9 The Spleen
Lymphatic system and body defenses
Nonspecific defenses
Do not distinguish one type of threat from another
7 types
Specific defenses
Protect against particular threats
Depend upon the activation of lymphocytes
SECTION 22-3 Nonspecific Defenses
Nonspecific Defenses, Physical barriers
Keep hazardous organisms outside the body
Includes hair, epithelia, secretions of integumentary and digestive systems
Figure 22.10 Nonspecific Defenses (Part 1 - Physical Barriers)
Nonspecific Defenses, Phagocytes
Remove cellular debris and respond to invasion by foreign pathogens
Monocyte-macrophage system - Fixed and free
Microphages – Neutrophils and eosinophils
Move by diapedesis
Exhibit chemotaxis
Figure 22.10 Nonspecific Defenses(Part 2 - Phagocytes)
Nonspecific Defenses, Immunological surveillance
Constant monitoring of normal tissue by NK cells
NK cells
Recognize cell surface markers on foreign cells
Destroy cells with foreign antigens
NK cell activation
Recognition of unusual surface proteins
Rotation of the Golgi toward the target cell and production of perforins
Release of perforins by exocytosis
Interaction of perforins causing cell lysis
Figure 22.10 Nonspecific Defenses(Part 3 - Immunological Surveillance)
Figure 22.11 How Natural Killer Cells Kill Cellular Targets
Nonspecific Defenses, Interferons (cytokines)
Small proteins released by virally infected cells
Trigger the production of antiviral proteins
Three major types of interferons are:
Alpha– produced by leukocytes and attract/stimulate NK cells
Beta– secreted by fibroblasts causing slow inflammation
Gamma – secreted by T cells and NK cells stimulate macrophage activity
Figure 22.10 Nonspecific Defenses(Part 4 - Interferons)
Nonspecific Defenses, Complement system
Cascade of ~11 plasma complement proteins (C)
Destroy target cell membranes
Stimulate inflammation
Attract phagocytes
Enhance phagocytosis
Complement proteins interact with on another via two pathways
Classical
Alternative
Figure 22.10 Nonspecific Defenses(Part 5 - Complement System)
Figure 22.12 Complement Activation
Nonspecific Defenses, Inflammation
Localized tissue response to injury producing
Swelling
Redness
Heat
Pain
Effects of inflammation include
Temporary repair of injury
Slowing the spread of pathogens
Mobilization of local, regional, and systemic defenses
Figure 22.10 Nonspecific Defenses(Part 6 - Inflammatory Response)
Figure 22.13 Inflammation
Nonspecific Defenses, Fever
Maintenance of a body temperature above 37.2oC (99oF)
Pyrogens reset the hypothalamic thermostat and raise body temperature
Pathogens, toxins, antigen-antibody complexes can act as pyrogens
Figure 22.10 Nonspecific Defenses(Part 7 - Fever)

Learning Objectives
Describe the structure and function of lymphatic cells, tissues and organs
List the body’s nonspecific defenses and describe the components and mechanisms of each
Define specific resistance and distinguish between cell-mediated immunity and antibody mediated immunity
Learning Objectives
Discuss the role of the T cell, B cell and antibodies in specific immunity
Describe the origin, development, activation and regulation of normal resistance to disease
Discuss the effects of stress and aging on the immune system
SECTION 22-1 An Overview of the Lymphatic System and Immunity
lymphatic system
The lymphatic system
Contains cells, tissues, and organs responsible for defending the body
Lymphocytes resist infection and disease by responding to
Invading pathogens such as bacteria or viruses
Abnormal body cells such as cancer cells
Foreign proteins such as toxins
Figure 22.1 The Components of the Lymphatic System
SECTION 22-2 Organization of the Lymphatic System
The lymphatic system consists of
Lymph
Lymphatic vessels
Lymphoid tissues and organs
Lymphocytes and supporting phagocytic cells
Functions of lymphatic system
Primary function is production, maintenance, and distribution of lymphocytes
Lymphocytes must:
Detect where problems exist
Be able to reach the site of injury or infection
Lymphatic vessels include
Lymphatic capillaries
Small lymphatic vessels
Major lymph-collecting vessels
Figure 22.2 Lymphatic Capillaries
Figure 22.3 Lymphatic Vessels and Valves
Major lymph-collecting vessels
Superficial and deep lymphatics
Thoracic duct
Cisterna chyli
Right lymphatic duct
Figure 22.4 The Relationship between the Lymphatic Ducts and the Venous System
Figure 22.4 The Relationship between the Lymphatic Ducts and the Venous System
Figure 22.4 The Relationship between the Lymphatic Ducts and the Venous System
Lymphocytes
Three classes of lymphocytes
T (thymus dependent) cells
B (bone marrow-derived) cells
NK (natural killer) cells
Lymphocyte production (lymphopoiesis)
Involves bone marrow, thymus, and peripheral lymphoid tissue
B cells and NK cells mature in bone marrow
T cells mature in the thymus
Figure 22.5 The Derivation and Distribution of Lymphocytes
Lymphoid tissue
Connective tissue dominated by lymphocytes
Lymphoid nodules
Lymphocytes densely packed in areolar tissue
Found in the respiratory, digestive, and urinary tracts
MALT (mucosa-associated lymphoid tissue)
Collection of lymphoid tissues linked with the digestive system
Figure 22.6 Lymphoid Nodules
Lymphoid organs
Lymph nodes – function in the purification of lymph
Afferent lymphatics – carry lymph to nodes
Efferent lymphatics – carry lymph from nodes
Deep cortex dominated by T cells
Outer cortex and medulla contains B cells
Figure 22.7 The Structure of a Lymph Node

Chapter 3, part 1
An Introduction to The Cellular Level of Organization
Learning Objectives
List the main points of the cell theory.
Describe the chief structural features of the cell membrane.
Describe the organelles of a typical cell, and give their specific functions.
Summarize the process of protein synthesis.
Describe the various transport mechanisms used by cells, and relate this to the transmembrane potential.
Describe the cell life cycle, mitosis and cellular differentiation.
SECTION 3-1 An Introduction to Cells
The cell theory states:
Cells are the building blocks of all plants and animals
Cells are produced by the division of preexisting cells
Cells are the smallest units that perform all vital physiological functions
Each cell maintains homeostasis at the cellular level
Homeostasis at higher levels reflects combined, coordinated action of many cells
Figure 3.1 The Diversity of Cells in the Human Body
Cell biology
Cytology, the study of the structure and function of cells
The human body contains both somatic and sex cells
Figure 3.2 The Anatomy of a Representative Cell
A typical cell
Is surrounded by extracellular fluid, which is the interstitial fluid of the tissue
Has an outer boundary called the cell membrane or plasma membrane
SECTION 3-2 The Cell Membrane
Cell membrane functions include:
Physical isolation
Regulation of exchange with the environment
Structural support
Figure 3.3 The Cell Membrane
The cell membrane is a phospholipid bilayer with proteins, lipids and carbohydrates.
Membrane proteins include:
Integral proteins
Peripheral proteins
Anchoring proteins
Recognition proteins
Receptor proteins
Carrier proteins
Channels
Figure 3.4 Membrane proteins
Membrane carbohydrates form the glycocalyx
Proteoglycans
Glycolipids
Glycoproteins

Chapter 18, part 3
The Endocrine System
SECTION 18-6 The Adrenal Glands
Adrenal cortex
Manufactures steroid hormones (corticosteroids)
Cortex divided into three layers
Zona glomerulosa (produces mineralocorticoids)
Zona fasciculate (produces glucocorticoids)
Zona reticularis (produces androgens)
Figure 18.16 The Adrenal Gland
Figure 18.17 Adrenal Abnormalities
Adrenal medulla
Produces epinephrine (~75 - 80%)
Produces norepinephrine (~25-30%)
SECTION 18-7 The Pineal Gland
Pineal gland
Contains pinealocytes
Synthesize melatonin
Suggested functions include inhibiting reproductive function, protecting against damage by free radicals, setting circadian rhythms
SECTION 18-1 The Pancreas
The pancreatic islets
Clusters of endocrine cells within the pancreas called Islets of Langerhans or pancreatic islets
Alpha cells secrete glucagons
Beta cells secrete insulin
Delta cells secrete GH-IH
F cells secrete pancreatic polypeptide
Figure 18.18 The Endocrine Pancreas
Insulin and glucagon
Insulin lowers blood glucose by increasing the rate of glucose uptake and utilization
Glucagon raises blood glucose by increasing the rates of glycogen breakdown and glucose manufacture by the liver
Figure 18.19 The Regulation of Blood Glucose Concentrations
SECTION 18-9 The Endocrine Tissues of Other Systems
The intestines
Produce hormones important to the coordination of digestive activities
The kidneys
Produce calcitriol and erythropoietin (EPO) and the enzyme rennin
Calcitriol = stimulates calcium and phosphate ion absorption along the digestive tract
EPO stimulates red blood cell production by bone marrow
Renin converts angiotensinogen to angiotensin I
Angiotensin I converted to angiotensin II in the lungs
Stimulates adrenal production of aldosterone
Stimulates pituitary gland release of ADH
Promotes thirst
Elevates blood pressure
Figure 18.20 Endocrine Functions of the Kidneys
Figure 18.20 Endocrine Functions of the Kidneys
The heart
Specialized muscle cells produce natriuretic peptides when blood pressure becomes excessive
Generally oppose actions of angiotensin II
The thymus
Produces thymosins
Help develop and maintain normal immune defenses
The gonads
Interstitial cells of the testes produce testosterone
Most important sex hormone in males
In females, oocytes develop in follicles
Follicle cells produce estrogens
After ovulation, the follicle cells form a corpus luteum that releases a mixture of estrogens and progesterone
Adipose tissues secrete
Leptin, a feedback control for appetite
Resistin, which reduces insulin sensitivity
SECTION 18-10 Patterns of Hormonal Interaction
Hormones often interact, producing
Antagonistic (opposing) effects
Synergistic (additive) effects
Permissive effects (one hormone is required for the other to produce its effect)
Integrative effects (hormones produce different but complimentary results)
Hormones and growth
Normal growth requires the interaction of several endocrine organs
Six hormones are important
GH
Thyroid hormones
Insulin
PTH
Calcitriol
Reproductive hormones
Hormones and stress
Stress = any condition that threatens homeostasis
GAS (General Adaptation Syndrome) is our bodies response to stress-causing factors
Three phases to GAS
Alarm phase (immediate, fight or flight, directed by the sympathetic nervous system)
Resistance phase (dominated by glucocorticoids)
Exhaustion phase (breakdown of homeostatic regulation and failure of one or more organ systems)
Figure 18.21 The General Adaptation Syndrome
Figure 18.21 The General Adaptation Syndrome
Figure 18.21 The General Adaptation Syndrome
Hormones and behavior
Many hormones affect the CNS
Changes in the normal mixture of hormones significantly alters intellectual capabilities, memory, learning and emotional states
SECTION 18-11 Aging and Hormone Production
Endocrine system
Few functional changes with age
Chief change is a decline in concentration of reproductive hormones
You should now be familiar with:
The major chemical classes and general mechanisms of hormones.
The location and structure of the pituitary gland, and its structural and functional relationships with the hypothalamus.
The location and structure of each of the endocrine glands.
The hormones produced by each of the endocrine glands, and the functions of those hormones.
You should now be familiar with:
The functions of the hormones produced by the kidneys, heart, thymus, testes, ovaries and adipose tissue.
How hormones interact to produce coordinated physiological responses.

Chapter 18, part 2
The Endocrine System
Hypophyseal portal system
All blood entering the portal system will reach the intended target cells before returning to the general circulation
Figure 18.7 The Hypophyseal Portal System
Figure 18.8 Feedback control of Endocrine Secretion
Figure 18.8 Feedback control of Endocrine Secretion
Hormones of the adenohypophysis
Thyroid stimulating hormone (TSH)
Triggers the release of thyroid hormones
Thyrotropin releasing hormone promotes the release of TSH
Adrenocorticotropic hormone (ACTH)
Stimulates the release of glucocorticoids by the adrenal gland
Corticotrophin releasing hormone causes the secretion of ACTH
Hormones of the adenohypophysis
Follicle stimulating hormone (FSH)
Stimulates follicle development and estrogen secretion in females and sperm production in males
Leutinizing hormone (LH)
Causes ovulation and progestin production in females and androgen production in males
Gonadotropin releasing hormone (GNRH) promotes the secretion of FSH and LH
Hormones of the adenohypophysis
Prolactin (PH)
Stimulates the development of mammary glands and milk production
Growth hormone (GH or somatotropin)
Stimulates cell growth and replication through release of somatomedins or IGF
Growth-hormone releasing hormone (GH-RH)
Growth-hormone inhibiting hormone (GH-IH)
Melanocyte stimulating hormone (MSH)
May be secreted by the pars intermedia during fetal development, early childhood, pregnancy or certain diseases
Stimulates melanocytes to produce melanin
The posterior lobe of the pituitary gland (neurohypophysis)
Contains axons of hypothalamic nerves
neurons of the supraoptic nucleus manufacture antidiuretic hormone (ADH)
Decreases the amount of water lost at the kidneys
Elevates blood pressure
The posterior lobe of the pituitary gland (neurohypophysis)
Neurons of the paraventricular nucleus manufacture oxytocin
Stimulates contractile cells in mammary glands
Stimulates smooth muscle cells in uterus
Figure 18.9 Pituitary Hormones and Their Targets
SECTION 18-4 The Thyroid Gland
The thyroid
Lies near the thyroid cartilage of the larynx
Two lobes connected by an isthmus
Figure 18.11 The Thyroid Gland
Figure 18.11 The Thyroid Gland
Thyroid follicles and thyroid hormones
Thyroid gland contains numerous follicles
Release several hormones such as thyroxine (T4) and triiodothyronine (T3)
Thyroid hormones end up attached to thyroid binding globulins (TBG)
Some are attached to transthyretin or albumin
Figure 18.12 The Thyroid Follicles
Figure 18.12 The Thyroid Follicles
Thyroid hormones
Held in storage
Bound to mitochondria, thereby increasing ATP production
Bound to receptors activating genes that control energy utilization
Exert a calorigenic effect
Cells of the thyroid gland
C cells produce calcitonin
Helps regulate calcium concentration in body fluids
Figure 18.13 Thyroid Disorders
SECTION 18-5 The Parathyroid Glands
Four parathyroid glands
Embedded in the posterior surface of the thyroid gland
Chief cells produce parathyroid hormone (PTH) in response to lower than normal calcium concentrations
Parathyroid hormones plus calcitriol are primary regulators of calcium levels in healthy adults
Figure 18.14 The Parathyroid Glands
Figure 18.15 The Homeostatic Regulation of Calcium Ion Concentrations

Chapter 2, part 1
The Chemical Level of Organization
Learning Objectives
Describe an atom and compare the ways atoms combine to form molecules.
Distinguish among the types of chemical reactions that are important to physiology.
Describe the role of enzymes in metabolism.
Distinguish between organic and inorganic compounds.
Explain the importance of water, pH and buffers to living systems.
Discuss the structures and functions of carbohydrates, lipids, proteins, nucleic acids and high energy compounds.
SECTION 2-1 Atoms, Molecules and Bonds
Atoms are the smallest stable units of matter
Subatomic particles
Protons = positive charge; weight of approximately 1 Dalton
Neutrons = no charge; weight similar to protons
Electrons = negative charge; weigh 1/1836th Dalton
Protons and neutrons are found in the nucleus; electrons occupy electron cloud
Atomic number = proton number; atomic mass = protons and neutrons
Isotopes are elements with similar numbers of protons but different numbers of neutron
Figure 2.1 Hydrogen Atoms
Electrons occupy a series of energy levels or electron shells.
The outermost electron shell determines the reactivity of the element.
Figure 2.2 Atoms and Energy Levels
Atoms combine through chemical reactions
Molecule = a chemical structure consisting of molecules held together by covalent bonds
Compound = a chemical substance composed of atoms of two or more elements
There are three types of bond: Ionic, covalent, and hydrogen
Ionic = attraction between positive cations and negative anions
Figure 2.3 Ionic Bonding
Covalent bonds exist between atoms that share electrons to form a molecule
Double covalent bond
Non-polar covalent bond
Polar covalent bond
Hydrogen bonds are weak forces that affect the shape and properties of compounds
Polar covalent bonds that occur when hydrogen covalently bonds with another element
Figure 2.5 Polar Covalent Bonds and the Structure of Water
Figure 2.6 Hydrogen Bonds
Matter and chemical notation
Matter can exist as a solid, liquid or gas
Depends on the interaction of the component atoms or molecules
Molecular weight is the sum of the atomic weights of the component atoms
Chemical notation
Short-hand that describes chemical compounds and reactions
See table 2.2 for examples of chemical notation
SECTION 2-2 Chemical Reactions
A chemical reaction occurs when reactants combine to generate one or more products
All chemical reactions in the body constitutes metabolism
Metabolism provides for the capture, storage and release of energy
Basic energy concepts
Work = movement of an object or change in its physical structure
Energy = the capacity to perform work
Kinetic energy is energy of motion
Potential energy is stored energy resulting from position or structure
Conversions are not 100% efficient, resulting in release of heat
Metabolism
Types of reaction
Decomposition
Synthesis
Exchange
Metabolism is the sum of all reactions
Through catabolism cells gain energy (break down of complex molecules)
Anabolism uses energy (synthesis of new molecules)
Reversible reactions
All reactions are theoretically reversible
At equilibrium the rates of two opposing reactions are in balance
Anabolism = catabolism
Enzymes, energy and chemical reactions
Activation energy is the amount of energy needed to begin a reaction
Enzymes are catalysts
Reduce energy of activation without being permanently changed or used up
Promote chemical reactions
Figure 2.7 Enzymes and Activation Energy
SECTION 2-3 Inorganic Compounds
Nutrients and Metabolites
Nutrients are essential chemical compounds obtained from the diet
Metabolites are molecules synthesized or broken down inside the body
These can be classified as organic or inorganic compounds
Organic compounds have carbon and hydrogen as their primary structural component
Inorganic compounds are not primarily carbon and hydrogen
Water and its properties
Water is the most important constituent of the body
Solution is a uniform mixture of two or more substances
Solvent is the medium in which molecules of solute are dispersed
Water is the solvent in aqueous solutions
Figure 2.8 Water molecules and solutions
Electrolytes undergo ionization
Compounds that interact readily with water are hydrophilic
Compounds that do not interact with water are hydrophobic
pH is a measure of the concentration of hydrogen ions solution
Neutral
Acidic
Basic
Acids and Bases
Acids release hydrogen ions into solution
Bases remove hydrogen ions from solution
Strong acids and strong bases ionize completely
Weak acids and weak bases do not ionize
Figure 2.9 pH and Hydrogen Ion Concentration
Salts and buffers
Salt = an electrolyte whose cation is not hydrogen and whose anion is not hydroxide
Buffers remove or replace hydrogen ions in solution
Buffer systems maintain the pH of body fluids

Here is 18-1. More detail to follow in class

Chapter 18, part 1
The Endocrine System
Learning Objectives
Compare the major chemical classes and general mechanisms of hormones.
Describe the location and structure of the pituitary gland, and explain its structural and functional relationships with the hypothalamus.
Describe the location and structure of each of the endocrine glands.
Learning Objectives
Identify the hormones produced by each of the endocrine glands and specify the functions of those hormones.
Describe the functions of the hormones produced by the kidneys, heart, thymus, testes, ovaries and adipose tissue.
Explain how hormones interact to produce coordinated physiological responses.
SECTION 18-1 Intercellular Communication
Endocrine versus Nervous system
Nervous system performs short term crisis management
Endocrine system regulates long term ongoing metabolic
Endocrine communication is carried out by endocrine cells releasing hormones
Alter metabolic activities of tissues and organs
Target cells
Paracrine communication involves chemical messengers between cells within one tissue
SECTION 18-2 An Overview of the Endocrine System
Endocrine system
Includes all cells and endocrine tissues that produce hormones or paracrine factors
Figure 18.1 The Endocrine System
Hormone structure
Amino acid derivatives
Structurally similar to amino acids
Peptide hormones
Chains of amino acids
Lipid derivatives
Steroid hormones and eicosanoids
Figure 18.2 A Structural Classification of Hormones
Hormones can be
Freely circulating
Rapidly removed from bloodstream
Bound to transport proteins
Mechanisms of hormone action
Receptors for catecholamines, peptide hormones, eicosanoids are in the cell membranes of target cells
Thyroid and steroid hormones cross the membrane and bind to receptors in the cytoplasm or nucleus
Figure 18.3 G Proteins and Hormone Activity
Figure 18.4 Hormone Effects on Gene Activity
Control of endocrine activity
Endocrine reflexes are the counterparts of neural reflexes
Hypothalamus regulates the activity of the nervous and endocrine systems
Secreting regulatory hormones that control the anterior pituitary gland
Releasing hormones at the posterior pituitary gland
Exerts direct neural control over the endocrine cells of the adrenal medullae
Figure 18.5 Three Methods of Hypothalamic Control over the Endocrine System
SECTION 18-3 The Pituitary Gland
Hypophysis
Releases nine important peptide hormones
All nine bind to membrane receptors and use cyclic AMP as a second messenger
Figure 18.6 The Anatomy and Orientation of the Pituitary Gland
The anterior lobe (adenohypophysis)
Subdivided into the pars distalis, pars intermedia and pars tuberalis
At the median eminence, neurons release regulatory factors through fenestrated capillaries
Releasing hormones
Inhibiting hormones

SECTION 17-4 Equilibrium and Hearing
Hearing
The special sense of hearing and equilibrium are provided by the inner ear which is a receptor complex located in the peterous part of the temporal bone of the skull
Equilibrium sensations inform us of the position of the head in space
Hearing enables us to detect and interpret sound waves
The basic mechanisms for both senses are hair cells, a mechanical sensors
The anatomy of the ear
Three anatomical regions
External ear
Middle ear
Inner ear
Both equilibrium and hearing are provided by receptors of the inner ear
Anatomy of the ear – External Ear: visible portion, collects and directs sound toward the middle ear: compostion
Auricle or pinnae surrounds the ear
External acoustic meatus ends on tympanic membrane
External ear
Includes the fleshy and cartilaginous auricle
This surrounds the external acoustic canal or ear canal
This is the passage way that ends on the tympanic membrane
Protective features found here in the form of ceruminous glands which produce cerumen
Figure 17.20 The Anatomy of the Ear
Middle ear
Communicates with pharynx via pharyngotympanic membrane
Middle ear encloses and protects the auditory ossicles
Figure 17.21 The Middle Ear
Middle Ear
Also called the tympanic cavity
It is separated from the external acoustic canal by the tympanic membrane
Communicates with the nasopharnyx through the auditory tube and the mastoid air cells
Also called the pharyngotympanic tube which permits equalization of air
Auditory Ossicles
Hammer
Anvil
Stirrup
What are the articulations?
Malleus attaches to the tympanic membrane
The stapes articulates on the oval window
How is sound carried?
It is the articulations of the hammer on the vibrating tympanic membrane that is passed to the stapes which moves up and down on the oval window
It is really a rocking motion on the stapes
This is a level design that amplifies sound because the tympanic membrane is heavier then the membrane of the oval window

What is the job of the inner ear?
The sense of equilibrium and hearing are provided by receptors of the inner ear
Remember that these receptors lie within a collection of fluid filled chambers known as the membranous labyrinth which is filled with an electrolytic soln called endolymph
Inner ear: bony labyrinth: function
Bony labyrinth surrounds and protects membranous labyrinth
Between the bony and membranous labyrinth is found perilymph (CSF)
What are the divisions of the bony labyrinth?
Vestibule: pair of membraneous sacs
Saccule
uticle
Semicircular canals
stimulated by rotation of the head
Cochlea
Provide the sense of hearing
Figure 17.22 The Inner Ear
Components of the inner ear: quick review: are what?
Vestibule contains the utricle and saccule
Semicircular canals contain the semicircular ducts
Cochlea contains the cochlear duct
Windows: two types: functions:
Round window separates the perilymph from the air spaces of the middle ear
Oval window connected to the base of the stapes
Basic receptors of inner ear are hair cells
Provide information about the direction and strength of stimuli
Receptors of the inner ear
These sensory receptors are called hair cells
These cells are surrounded by supporting cells and are monitored by sensory afferent fibers
The hair like structures have two components
Stereocilia: 80 – 100 present
Kinocilium: single large cilia
Only move when external forces push against them
What kind of information will these cilia provide?
Direction and strength of the mechanical stimulation and response varies depending on the location of the cilia
Types of stimulation can include:
Gravity or acceleration in the vestibule
Rotation in the semicircular canal
Sound in the cochlea

How is equilibrium information provided?
Provided by receptors of the vestibular complex
The information provided is based on rotational movements of the head
Thus the saccule and the utricle convey information with respect to gravity
They are stimulated by sudden acceleration (stop or start)

The semicircular ducts
Thus the sensory receptors are quiet during non movement
What is this movement?
The kinocilia and the sterocilia are embeded in the cupula
Cupula floats on the endolymph
The movement of ones head distorts the receptor processes
Movement is based on direction
When there is no further movement, the cupula returns to the rest position
Thus there is analysis of motion in three planes

What is the job of Utricle and Saccule?
Both provide information about equilibrium whether or not the body is stationary or moving
Equilibrium: The whole structure è otolith
Anterior, posterior and lateral semicircular ducts are continuous with the utricle
Each duct contains an ampulla with a gelatinous cupula and associated kinocilia and sterocilia (review)
Saccule and utricle connected by a passageway continuous with the endolymphatic duct
Terminates in the endolymphatic sac
Saccule and utricle have hair cells clustered in an oval structure called the maculae
Cilia contact the statoconia ( calcium carbonate crystals)
Figure 17.23 The Vestibular Complex
Figure 17.23 The Vestibular Complex
Figure 17.23 The Vestibular Complex
Vestibular neural pathway: How is monitoring achieved?
Hairs of the vestribular and semicircular ducts are monitored by sensory neurons located in the vestibular ganglia
Axons form the vestibular branch of the vestibular cocohlear nerve (VIII)
Synapses within the vestibular nuclei between the pons and the medulla oblongata
Job functions; 4 of them
Integrating sensory information about balance and equilibrium that arrives from both sides of the head
Relay information from the vestibular complex to the cerebellum
Relay information from the vestibular complexd to the cerebral cortex for a conscious position of position of head
Send motor commands to nuclei in brain stem and spinal cord

What kind of information is sent?
Reflexive motor commands that are issued are distributed to motor nuclei for cranial nerves III, IV, VI, and XI
Descend down the vestibularspinal tracts
Adjust muscle tone
Figure 17.24 Pathways for Equilibrium Sensation
Hearing
Cochlear duct lies between the vestibular duct and the tympanic duct
Hair cells of the cochlear duct lie within the Organ of Corti
Intensity is the energy content of a sound
Measured in decibels
Figure 17.25 The Cochlea
Figure 17.26 The Organ Of Corti
Hearing
The receptors of the cochlear duct provide the sense of hearing that enables us to detect soft sounds
Hair cells responsible for picking up this auditory sound
Location prevents them from responding to any other stimuli
Whole process is based on pressure waves
This is the fluctuations of perilymph which determine the frequency and intensity
Pathway of sound
Sound waves travel toward tympanic membrane, which vibrates
Auditory ossicles conduct the vibration into the inner ear
Tensor tympani and stapedius muscles contract to reduce the amount of movement when loud sounds arrive
Movement at the oval window applies pressure to the perilymph of the cochlear duct
Pressure waves distort basilar membrane
Hair cells of the Organ of Corti are pushed against the tectoral membrane
It is the distortion of the basiliar membrane pressing on the tectorial membrane that results in the generation of an action potential in the receptors
Figure 17.28 Sound and Hearing
Figure 17.29 Sound and Hearing
Neural pathway; location of the nerve fibers
Sensory neurons of hearing are located in the spiral ganglion of the cochlea
Afferent fibers form the cochlear branch of cranial nerve VIII
Synapse at the cochlear nucleus
The steps:
Sound waves arrive at the tympanic membrane
Tympanic membrane causes displacement of auditory ossciles
Stapes moves against the oval window
Pressure waves distort the basilar membrane
Vibration of the basilar membrane
Relay information along the afferent branch of the Vestibularcodhlear nerve VIII to the cochlear nucleus then crosses to opposite side of the brain to the inferior colliculus
Then to the thalamus and finally to the auditory cortex of the temporal lobe
You should now be familiar with:
The sensory organs of smell, and the olfactory pathways in the brain.
The accessory and internal structures of the eye, and their functions.
How light stimulates the production of nerve impulses, and the visual pathways.
The structures of the external and middle ear and how they function.
The parts of the inner ear and their roles in equilibrium and hearing.
The pathways for the sensations of equilibrium and hearing.