Final Exam Questions for Anatomy II PDF

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These are potential questions for a final exam covering all the material learned in AP2. These questions are from Dr. Amarcost. ...

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Fluid Homeostasis Body Fluid Distribution -Adults, Body Fluids constitute 50-60% (Body Mass) -Fluids are distributed among several components -2/3 (Intercellular Fluid) (ICF) -1/3 (Extracellular Fluid) (ECF) -80% of ECF is (Interstitial Fluid) (IF) -20% of ECF is (Blood Plasma) Fluid & Electrolyte Balance Both Fluid and Electrolyte Balance are components of Homeostasis Balance- Volume of Body Fluids. Components of body fluids Concentrations of solutes & pH of body fluids mainly by the kidneys Electrolytes- Inorganic compound that dissociates into ions in water. Often are Salts. (Ex. NaCl  Na + ClFunctions of Electrolytes -Carry Electrical Currents -Serve as enzyme Cofactors -Control Movement of water between fluid compartments -Water follows salts via Osmosis -Help maintain acid base balance (pH) Exchanges of body fluid among compartments -Barriers to exchange -Plasma membranes of cells -Capillary Walls -Merch of exchange (Some passive, some active) -Diffusion Osmosis

-Facilitated Transport -Active Transport In Kidneys -Filtration, Reabsorption, secretion Regulation of water Gain Metabolic water -Varies with metabolic rate (ATP demand) Small contribution to water gain -Ingested food Moderate contribution to water gain -Ingested Liquid Large contribution to water gain -Thirst center in brain stimulated by a decrease in blood volume and increase in osmolality of blood.

Regulation of water Loss GI, Tract, Lungs & Skin Varies with metabolic rate (Exercise) Moderate contribution to water Loss Various mechanics to reduce water loss – Kidneys Large Contribution to water loss Highly regulation via reabsorption of salts and water

Regulation of Fluid Homeostasis by Kidneys Urinary water loss- determines body fluid osmolality Regulation by ADH (Antidiuretic Hormone) Urinary Salt Loss (Mainly NaCl) – Determines body fluid volume Because water follows salt Via Osmosis Regulation by 3 Hormones

1. Atrial natriuretic peptide (ANP) 2. Angiotensin II 3. Aldosterone Hormone control of urinary salt loss if you ingest excess NaCl the concentration of Na+ and Cl- in EFC (Extracellular Fluid) increases, Increasing EFC volume as water follows salt via osmosis, increasing blood Volume. If Blood Volume increases more ANP is released by heart, less angiotensin II is released by kidney, and less aldosterone is released by adrenal gland. Increases ANP promotes Na+ and Cl- absorption in renal tubule while decreased angiotensin II inhibits Na+ and Cl- absorption in renal tubule and decreases Aldosterone inhibits in collecting duct, thus more Na+ and Cl- secreted in urine, water followers salt via salt via osmosis. Blood volume decreases.

Maintenance of Constant pH Also referred to as acid-base balance Acid  H+ (+) anion Base  OH- (+) cation pH measures the Concentration of H+ 0 = Acidic 7 = Neutral 14 ¿ Basic

(Dissociation in Water)

Metabolic processes often produce H+ as byproducts and lower pH Body must buffer then eliminate H+ to maintain. Mechanisms of pH Balance Buffers Exhalation of (O2 in Lungs) Excretion of (H+ in the Kidneys) Buffers- fast rate of response Buffers bind to H+ (Removing it from the solution but not the body) 3 Main Buffer Systems 1. Protein Buffer System (ECF or ICF) 2. Phosphate Buffer System (ICF) 3. Carbonic acid/ Bicarbonate Buffer System (EFC, Mainly Blood) Protein Buffer System

Buffers IF and EF Amino Acids of proteins have: carboxyl group (COOH) Amino Group (nH2) *If pH goes (UP) the H+ concentration goes (DOWN) *If pH goes (DOWN) H+ concentration goes (UP)

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Protein Buffers can rise or fall in pH Phosphate Buffer System Buffers intracellular fluid In two atoms 1. H2PO4m (Dihydrogen Phosphate) 2. HPO4 (Monohydrogen Phosphate) *If pH goes (UP) H+ concentration goes (DOWN) *If pH goes (Down) H+ concentration goes (UP)

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So phosphate System can buffer rise and fall in pH Carbonic Acid Bicarbonate Buffer System Buffers extracellular fluid CO2 from tissues is carried in blood mainly as HCO3 (Bicarbonate) * If pH goes (UP) H+ concentration goes (DOWN) *If pH goes (DOWN) H+ concentration goes (UP)

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So Carbonic Acid Bicarbonate System can buffer pH rise and fall Buffers remove H+ from solution, NOT the body Exhalation of CO2 and excretion of H+ removes H+ Exhalation of CO2 in lungs Moderate rate of response Removes carbonic acid (Hense some H+) and raises pH Increase in CO2 in tissues leads to fall in pH (H+ concentration goes UP) CO2 + H2O  H2CO3 (Carbonic Acid) H2CO3 + H+  HCO3 (Bicaronate Acid) Decrease in CO2 in lungs leads to rise in pH (H+ Concentration goes DOWN)

HCO3 + H+  H2CO3 H2CO3  CO2 + H20 (Which are exhaled)

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So lungs effectively remove some H+ from Body Rate of ventilation of lungs can affect pH Balance Excretion of H+ in Kidneys Slow rate of Response Removes a significant amount of H+ and raises pH of Blood H+ Excretions in the Kidneys Most excess H+ is removed by the Kidneys Some H+ is secreted into filtrate in Proximal and Distal Tubes Most H+ secretes into urine by intercalated cells in the walls of the collecting ducts Intercalated cells have proton pumps (H+ ATPases) in apical membrane (Lumen of collecting ducts) so the cells pump H+ one direction (Into Urine)

The Reproductive System Male Reproductive System Testes: Accessory sex glands, Seminal vesicles, Prostate, Bulbourethral Glands. Accessory ducts: Epididymis, Ductus Deferens, Ejaculatory Ducts, Urethra Accessory Structures: Scrotum, Penis Testes Divided into 2 Lobules- each with 1-3 seminiferous tubules. Leydig cells (Interstitial cells) – Between seminiferous tubules, they secrete testosterone (T) Seminiferous tubules include 2 cell types 1. Spermatogonia ( spermatogonium) – Produce sperm cells (spermatogenesis) 2. Sertoli cells – Provide nutrients to developing sperm cells, create blood testis barrier- which prevents immune response against sperm cells.

Review of Gametogenesis Diploid (2) germ cells in adult produce haploid (1) gametes via meiosis in the gonads. Meiosis occurs in two different stages. Gametogenesis includes 1. Spermatogenesis 2. Oogenesis Spermatogenesis in males Testes produce sperm (Spermatozoa) Begins in Puberty Stages of Spermatogenesis 1. 2. 3. 4. 5. 6. 7.

Spermatogonia (2) stem cells Primary spermatocytes (2) Meiosis I Two Secondary Spermatocytes (1) Meiosis II Four Spermatids (1) Spermatids mature- sperm cells (spermatozoa) As cells mature they move from superficial to deep within seminiferous tubule (Then into lumen) Sperm Cells Head: Acrosome- contains digestive enzymes Nucleus- Contains chromosomes Tail: Neck- contains centrioles Middle Piece: contains mitochondria Principal Piece: Microtubules for locomotion End Piece: Microtubules

Hormonal Regulation of Testes

1. Hypothalamus releases gonadotropin releasing hormone (GnRH) 2. GnRH stimulates anterior pituitary to release luteinizing hormone (LH) and folliclestimulating hormone (FSH)

3. LH stimulated Leydig cells to release Testosterone (T) 4. FSH and T together stimulate Sertoli cells to release androgen- binding protein (ABP) 5. ABP maintains high level of T in seminiferous tubules 6. In seminiferous tubules, T stimulates final stages of Spermatogensis

Other Functions of Testosterone (T) Simulates prenatal development of primary male sexual charateristics Ex. Penis Stimulates development of secondary male sexual characteristics at puberty (Ex. Facial Hair) Stimulates male’s sexual behavior (Libido) Stimulates protein synthesis- males often have greater muscle mass than females.

Accessory Sex Glands Seminal Vesicles- secretes fluid (60% of semen Vol.) Including fructose for ATP production in sperm Slightly Alkaline (pH 7.2- 7.7) To Buffer acidic environment of male urethra and female vagina Prostate- Secretes fluid (25% of semen Vol.) Including critic acid for ATP production in sperm Bulbourethral Glands (Cowper’s glands) – Secrete Fluid including mucus for lubrication in urethra. Semen Contains sperm and seminal fluid Vol. of typical ejaculation is 2.5- 5ml Typical range for sperm count is 50-150 million/ml

*Pathway of Sperm in Testis* -Lumen of seminiferous tubule -Straight tubules

-Rete testis -Efferent Ducts Pathway of Sperm and Semen in Accessory Ducts -Ductus epididymis- site of sperm maturation and storage -Ductus deferens (Vas deferens) -Ejaculatory Duct- After duct from seminal vesicle enters ductus deferens -Urethra Scrotum Spermatogenesis is most efficient at 2-3 degrees Celsius below body core temp Scrotum allows testes to be outside of body cavity Contraction/ relaxation of muscles in wall of scrotum control temp of testes. Distance of testes from body (heat conduction) Surface area of scrotum (heat loss) Penis Three Cylindrical Masses -Corpus Cavernosa Penis (2) -Corpus Spongiosum Penis (1) – Surrounds the Urethra All 3 Masses contain Erectile tissue- expandable blood sinuses

Female Reproductive System -Ovaries -Uterine Tube (fallopian tube) (Oviduct) -Uterus (Womb) -Vagina -Vulva (Collective term for external structures) -Mammary Glands

Anatomy of the Ovaries Four Layers of the Ovaries 1. 2. 3. 4.

Germinal epithelium (outer covering) Tunica Albuginea (connective tissue) Ovarian Cortex- follicles develop here Ovarian Medulla- contains blood and lymph vessels and nerves (Medulla- outer layer/ Cortex- inner layer) Function of the Ovaries Functions: -Produce gametes (oocytes)- Developing gamete (oocyte) is surrounded by layers of other cells (follicle) -Produce and secrete hormones: including Estrogen and Progesterone Review of Gametogenesis Diploid Adult  Haploid gametes via Meiosis in gonads Spermatogenesis in Male Testes  Sperm Begins at Puberty Oogenesis  oocytes Begins before birth (Prenatal), resumes at puberty (monthly) Developing oocyte is surrounded by associated cells (follicle) Thus, oogenesis (development of gamete) occurs simultaneously with follicular development (development of cells that surround the gamete) Stages of follicular development Primordial follicle Primary follicle Secondary follicle Mature (Graafian) follicle- Ruptures to release secondary oocyte from ovary (Ovulation) 5. Corpus Luteum – After secondary oocyte has been released, produces and secretes hormones. 6. Corpus albicans- Fibrous scar tissue. 1. 2. 3. 4.

Prenatal Stages of oogenesis and follicular development

Oogonium (2) Primary oocyte (2)- Enters prophase of meiosis I, becomes surrounded by primordial follicle, becomes dormant until puberty Oogonia do not produce additional primary ooctyes after birth. Many Primary oocytes degenerate via atresia 200,000 to 2 million at birth. About 40,000 at puberty About 400 will mature and ovulate. Stages of oogenesis and follicular development occurring monthly after puberty

-Resumption of oogenesis stimulated by LH and FSH -Follicular development (Cell growth and differentiation) (Primary oocyte remains unchanged) -Primordial follicle -Primary follicle -Secondary follicle -Mature follicle -Primary oocyte (2) in mature follicle -Completes meiosis I -Gives rise to two (1) cells of unequal size -Large Cell: Secondary oocyte (1) -Small Cell: First polar body (Degenerates) -Secondary oocyte (1) Begins Meiosis II -Pauses at end of metaphase of meiosis II -Mature follicles ruptures and releases secondary oocyte from ovary into pelvic cavity (ovulation) -Secondary oocyte (1) enters uterine tube

-If it isn’t fertilized, it degenerates -If fertilization begins (sperm penetrates oocyte) then oogenesis resumes. -Secondary oocyte (1) Completes meiosis II -Gives rise to two (1) cells of unequal size Large cell: ovum (Mature egg) (1) Small cell: Second polar body (Degenerates) Only then do nuclei of sperm and egg unite to complete fertilization and form a zygote (2)

Comparison of Spermatogenesis and Oogenesis Spermoatogenesis- only primary spermatocyte  four sperm Males produce four small, cheap gametes Begins at Puberty Leydig cells produce sex hormone

Oogenesis- One primary oocyte  one ovum Females produce one large, expensive gamete Begins before birth Resumes monthly after puberty Pauses after fertilization begins Corpus luteum produces sex hormones

Uterine (Fallopian) Tube or oviduct

Function: Movement of fimbriae, sweeps secondary oocyte into uterine tube. Secondary oocyte. Ovum moved along uterine tube by Peristalsis of smooth muscles Ciliary movement of epithelium

Fertilization usually occurs in ampulla Anatomy of Uterus 3 Tissue Layers 1. Perimetrium 2. Myometrium- Smooth muscle for labor and childbirth 3. Endometrium- Highly vascularized for development of placenta 2 Layers of Endometrium 1. Stratum Basalis- Permanent 2. Stratum Functionalis – Lost during Menstruation Function of Uterus: -Site of implantation of zygote -Site of development of fetus -Mucus of cervix changes ovulation -Less viscous, more alkaline -More hospitable for sperm Vagina Acidic environment hostile to pathogen (and Sperm) Vulva Structures and male homologs Female: Labia major/ Male: Scrotum Female: Labia minor/ Male Penis Female: Clitoris/ Male: Penis Accessory Glands Glands and male homologs Female: Paraurethral (Skenes’s) glands/ Male: Prostate (Secretes mucus for lubrication) Vestibular (Bartholin’s) glands/ Male: Bulbourethral (Secretes mucus for lubrication)

Female reproductive cycle Includes: Ovarian Cycle- Events that occur in the ovary Uterine Cycle- Events that occur in the endometrium of uterus Typically, 28 days Regulated by hormones of the Endocrine System

Hormonal Regulation of Female Reproductive cycle Hypothalamus secretes GnRH GnRH stimulates Anterior pituitary to secrete FSH and LH FSH initiates development of ovarian follicles FSH and LH stimulate further development of ovarian follicle LH triggers ovulation FSH and LH stimulate corpus luteum to secrete estrogens and progesterone Progesterone inhibits GnRH, FSH, and LH Other Roles of Estrogen Stimulates prenatal development of primary female sexual characteristics (Ex. Vagina) Stimulates development of secondary female sexual characteristics at puberty (Ex. Breast) Stimulates Protein synthesis- Maintains bone mass Lowers Blood cholesterol Other Female Hormones Progesterone- stimulates development of stratum functionalis Relaxin- inhibits contraction of myometrium Inhibin- Inhibits FSH and LH

Menstrual Phase (days 1-5)

Events in Ovaries: Increase in FSH stimulates several primordial follicles to begin developing into primary follicles and then into secondary follicles. (this process may take several months) Events in Uterus: Decrease in Progesterone and estrogens stimulate loss of stratum functionalis of endometrium and thus menstrual flow Preovulatory Phase (days 6-13) Events in Ovaries: a single secondary follicle outgrows other to become dominant follicle. Increase in estrogens and inhibin (secreted by dominant follicle) cause atresia of other secondary follicles. Dominant follicle develops into mature (Graafian Follicle) Events in Uterus: Increase in estrogens stimulate development of new stratum functionalis. Ovulation (day 14) Peak in estrogens stimulates increased Secretion of GnRH, LH, and FSH *Estrogen have positive impact on (GnRH, LH, FSH) Peak in LH stimulates ovulation Postovulatory Phase (days 15-28) Events in Ovaries: Mature Follicle becomes Corpus luteum Peak in LH stimulates corpus luteum to secrete progesterone, estrogens, relaxin and inhibin. Peak in progesterone inhibits secretion of GnRH, LH, and FSH *Progesterone has a negative impact on GnRH, LH and ESH (even in presence of estrogens) If secondary oocyte is not fertilized Then corpus luteum degenerates into corpus albicans

Decrease in progesterone and estrogens, relaxin stimulates increased secretion of GnRH, LH, and FSH for next cycle. Events in Uterus: Peak in progesterone and estrogens stimulates further development of stratum functionalis

Possible mechanism for regulation onset Puberty

Leptin levels rise in proportion to increasing adipose tissue mass throughout child hood. At puberty, leptin reaches some threshold level- signaling that body has accumulated enough adipose tissue mass (Energy reserves) to support a pregnancy Leptin levels above threshold stimulate release of GnRH by hypothalamus and thus one set of female reproductive cycle....