bmsp 2136 exam 5

mitosis

the cell division undergone by all body (somatic) cells that are capable of division; produces daughter cells identical to mother cells

product of mitosis

two diploid daughter cells that are genetically identical to the mother cell

cells that undergo mitosis

all body (somatic) cells that are capable of division

cells that undergo meiosis

in cells destined to become gametes

primary sex organs

gonads (ovaries in females, testes in males)

gonad secretions

sex hormones including testosterone, estrogens, gametes (sex cells- sperm & ova)

accessory reproductive organs

additional organs & structures that contribute to functioning of reproductive system

zygote

the cell that is formed from fusing of ovum & sperm; will eventually divide to produce all the cells in a new individual

product of meiosis

four genetically unique, haploid daughter cells

amount of chromosomes in a human cell

46 chromosomes, 23 pairs

diploid

2n, a cell w/ 23 pairs of homologous chromosomes

meiosis I

early prophase I, mid-to-late prophase I, metaphase I, anaphase I, telophase I

meiosis II

prophase II, metaphase II, anaphase II, telophase II

early prophase I

chromosomes form w/ two sister chromatids

mid-to-late prophase I

during synapsis, homologous chromosomes form tetrads & crossing over occurs

metaphase I

tetrads align randomly at equator (random orientation)

anaphase I

random orientation in metaphase I leads to independent assortment

telophase I

cytokinesis may follow, resulting in two genetically different haploid cells w/ sister chromatids still attached

prophase II

chromosomes remain condensed

metaphase II

chromosomes line up along equator

anaphase II

sister chromatids separate

telophase II

cytokinesis follows

homologous pair

a set of maternal & paternal chromosomes w/ the same genes

sister chromatids

a cell w/ 2 identical copies of its chromosomes

allele

one of two or more versions of a DNA sequence at a given genomic location (locus) on a chromosome

chromatin

noncondensed form of DNA

mitosis

interphase, prophase, metaphase, anaphase, telophase

male gonads

testes

location of testes

outside the abdominopelvic cavity

scrotum

saclike structure where the testes are located in

amount of seminiferous tubules that are in each lobule

1-4

functions of testes

produce sperm cells & secrete androgen hormones (testosterone)

cells found in seminiferous tubules

spermatogenic cells & sustentacular cells

spermatogenic cells

form sperm

sustentacular cells or burse cells

have several functions that support sperm production

supporting cells surrounding spermatogenic cells

large cells that extend from the basement to the lumen of the tubule & are bound to one another by tight junctions

interstitial cells

cells found between seminiferous tubules

produce & secrete androgens, mostly testosterone, into the ISF

straight tubule

formed when seminiferous tubules merge

rete testis

where sperm flows after straight tubule

efferent ductules

where sperm flows after rete testis

testicular artery

artery that serves the testicles

pampiniform venous plexus

veins that drain the blood from the testicles

network of veins

ducts that the sperm passes through after leaving the testis

epididymis, ejaculatory duct, urethra

ejaculation

the process by which semen is expelled from the penis

epididymis

functions in sperm maturation & storage

regions of epididymis

head, body, tail

length of ductus epididymis & importance of this for function

6 m (19.7 ft); very tightly coiled & twisted to fit into epididymis

path of ductus deferens

enters the pelvic cavity through inguinal canal → lateral side of bladder → over ureter → posterior bladder → ampulla

ampulla

enlarged end of the ductus deferens

ejaculatory duct

where sperm travels after the ampulla

located at junction of ampulla & the duct of an accessory gland (seminal vesicles)

prostate gland

gland that the ductus deferens travels through

where sperm travels after the prostate gland

urethra

male urethra

three regions include prostatic, membranous, & spongy

root

internal portion of the penis

shaft

external portion of the penis

glans penis

end of penis where external urethral orifice is located

prepuce

anatomical term for foreskin

circumcision

procedure where prepuce is removed

corpora

three bodies of erectile tissue in the penis; first two are corpora cavernosa & third is corpus spongiosum

composed of a spongy network of CT & SM w/ vascular spaces

corpus spongiosum

forms the bulb of the penis

corpora cavernosa

forms the crus

cause of the penis enlarging during sexual excitement

vascular spaces fill w/ blood → penis enlarges & becomes rigid

nerve supply to penis

innervated by many sensory & motor fibers- PS & S nerves

perineum

bordered by pubic symphysis, ischial tuberosities, & coccyx

semen

milky white, somewhat sticky mixture of sperm & fluids from the testes, seminal vesicles, prostate, bulbourethral glands, & urethral glands

what does the duct from the seminal vesicle merge with to form the ejaculatory duct

ductus deferens

seminal vesicle

produces seminal fluid

what is formed by the seminal vesicle and ductus deferens merging

ejaculatory duct

color of seminal fluid

yellow

pH of seminal fluid

alkaline/basics

components of seminal fluid

fructose, prostaglandins, coagulating proteins, & enzymes

size of prostate gland

approximately egg-shaped

what typically happens to the prostate gland w/ age

enlarges

why would an enlarged prostate gland cause a problem w/ urination

pushes on urethra

color of prostatic fluids

milky

pH of prostatic fluids

alkaline/basic

function of enzymes found in prostatic fluid

dissolve the clot of semen that initially forms in the female reproductive tract so that sperm can move deeper into the tract

size of bulbourethral glands

small marble (1 cm or 0.4 in)

when does the bulbourethral gland release its secretion

sexual stimulation

function of bulbourethral gland secretion

alkaline fluid that helps neutralize any acidic urine & lubricates the urethra for the passage of ejaculate

major component of semen

seminal fluid

secondary largest component of semen

prostate fluid

capacitation

process where sperm undergoes changes that enable them to penetrate & fertilize on an immature female gamete

septum

divides the scrotum into two compartments

raphe

marks location of septum externally by a ridgelike seam at the midline, continues anteriorly along the ventral side of penis & posteriorly to anus

dartos muscle

smooth muscle layer in the scrotum

spermatic cord

contains layers of fascia & contains ductus deferens

cremastor muscle

smooth muscle found in spermatic cord

inguinal canal

passageway into the abdomen

inguinal ring

body cavity to scrotum

main component of all body fluids

water

electrolyte

substance that disassociates into ions when placed in water

most common electrolytes discussed

Na+, K+, Ca+

ion

atom or molecule w/ a net electric charge due to an unequal # of electrons & protons

electrolyte balance

the amount of electrolytes gained through the diet is equal to that lost from the body

importance of fluid balance in determining electrolyte balance

determines concentration of ions in body

acid

chemical that disassociated in water to release an H+

base

chemical that accepts an H+ in solution

most common base in the body

bicarbonate ion (HCO3-)

spermatogenesis

process where sperm cells develop

process of spermatogenesis

1. spermatogonium differentiates into a primary spermatocyte

2. one primary spermatocyte undergoes meiosis I to produce two haploid secondary spermatocytes

3. the two secondary spermatocytes each undergo meiosis II to produce a total of four haploid spermatids

4. spermatids elongate as they begin spermiogenesis

5. spermatids migrate to the epididymis and continue to undergo spermiogenesis to eventually become mature sperm cells