BSCI202 STUDY GUIDE FINAL

what are the male primary sex organs?

male GONADS= TESTES

primary sex organs function

-Produce male gametes called spermatozoa

-Produce male steroid hormones called androgens (DHEA, Androstenedione and Testosterone)

male accessory reproductive ducts and glands

4 ducts: Epididymides (2), Vasa Deferentia (2), Ejaculatory ducts (2), Urethra (1)

3 glands: seminal vesicles (2), prostate gland (1), bulbourethral glands (2)

name the membrane surrounding each testis

outer tunica vaginalis and inner tunica albuginea

outer tunica vaginalis

surrounds the testis as an outer protective layer

inner tunica albuginea

-partitions the testis into wedge-like lobules

-Each lobule contains seminiferous tubules = structural units of testis

seminiferous tubules

spermatogenesis occurs here and they are referred to as sperm factories

leydig cells

inside the testes are the endocrine cells stimulated by LH to produce the androgens

3 types of androgens

DHEA, Androstenedione, testosterone

testosterone as an androgen

testosterone is converted in the bloodstream to the more potent form called dehydrotestosterone by the enzyme, 5 alpha reductase

DHEA

estriol

Function: development of external genitalia (especially during fetal development), puberty changes like facial/body hair and prostate growth

androstenedione

estrone

Function: serves as a precursor (triggered by LH)

LH reacts directly on leydig cells in order to release testosterone

prenatal biological actions of DHT

DHT stimulates the differentiation of of male internal and external genitalia

-Thus androgen deficiency or androgen receptor dysfunction or 5 alpha reductase deficiency in the male fetus will result in the differentiation of the female external genitalia.

-The female fetus with high levels of androgens as in CAH, will result in the differentiation of the male external genitalia

postnatal biological actions of DHT

stimulates the male secondary sex characteristics

-Stimulates the growth and function of the male genitalia

-Stimulates bone growth-> growth spurt to increase bone density (anabolic effect)

-Stimulates skeletal muscle growth-> increase muscle mass and strength (anabolic effect)

-Stimulates EPO release-> increases RBC number= increases the hematocrit (explains why testosterone is used in the treatment of anemia due to decreased RBC)

-Stimulates growth of the laryngeal cartilages (adams apple)-> deepening of the voice

-Stimulates growth of facial hair and body hair

Activates the apocrine (odoriferous) sweat glands-> secretion is responsible for body odor

-Stimulates sebaceous glands to secrete more sebum-> acne

-Stimulates libido (sex drive) in both males and females

-Stimulates spermatogenesis: sperm production; sperm are the male gametes required for reproduction

function of the scrotum

-Testes are located inside the scrotum: this hangs outside from the perineum

-The septum divides the scrotum and provides a compartment for each testis

function of the cremaster muscle and dartos muscle in cold weather

he cremaster muscle contracts pulling the scrotum closer to the body for warmth the dartos muscle contracts to cause the surface of the scrotum to wrinkle, reducing heat loss

function of the cremaster muscle and the dartos muscle in hot weather

the cremaster muscle relaxes causing the scrotum hangs lower away from the body; the DARTOS muscle relaxes and the skin becomes flaccid and the surface area of the scrotum increases to increase heat loss

functions of the testes

1. Production of the male sex steroid hormones known as the androgens

Major androgen is testosterone

Leydig cells inside the testes are the endocrine cells

2. Spermatogenesis: production of the male gametes

-intrascrotal temp must be 34 degrees C for optimal sperm production

spermatogenesis 3 phases

spermatocytogenesis, meiosis, spermiogenesis

seminiferous tubules

highly coiled tubules inside testes- the sites for sperm production referred to as sperm factories (produce 100-400 million sperm/day)

are spermatogonia haploid or diploid?

diploid

are primary spermatocyte haploid or diploid?

diploid

are secondary spermatocyte haploid or diploid?

haploid

are spermatids haploid or diploid?

haploid

are spermatozoa haploid or diploid?

haploid

spermatogenesis phases

64-72 days

mitosis in spermatogenesis

-spermatogonium (2n) undergoes mitosis to yield 2 identical daughter cells called type A and type B

-Type A replenishes spermatogonial stock

-Type B cell moves toward the lumen of the seminiferous tubules and its referred to as the primary spermatocyte (2n= diploid)

spermatogenesis meoisis phase

-1st meiotic division (reduction division)- primary spermatocyte completes the first meiotic division to yield 2 haploid cells of equal size called secondary spermatocytes (n=23)

-2nd meiotic division (equational division)- 2 secondary spermatocytes complete the second meiotic division to yield 4 haploid cells of equal cells called spermatids (n)- round with superfluous cytoplasm and non-motile

spermiogenesis phase in spermatogenesis

- first maturation process that converts the round into the spermatids into the stream-lined spermatozoa that are capable of swimming

-contains head, midpiece and tail

spermiogenesis head

contains the haploid nucleus with an acrosome= helmet-like structure capping the head and contains hydrolytic enzymes

spermiogenesis midpiece

contains mitochondria- for aerobic respiration to produce ATP to support "swimming"

spermiogenesis tail= flagellum

composed of microtubules and contains disulfide linkages required for whiplashing movements during "swimming"

blood testis barrier

The sustentacular (sertoli) cells are the target cells for FSH- sustentacular cells form the blood-testis barrier that surrounds the developing spermatogenic cells in the seminiferous tubules

significance of blood testis barrier

prevents contact between cells of the specific immune system and the developing spermatogenic cells in the seminiferous tubules; these spermatogenic cells are developing after the specific immune cells have been programmed to differentiate between self and non self antigens. Cells of the specific immune system will attack and destroy the spermatogenic cells if they come into direct contact

what cells form the blood testis barrier

sustentacular cells

sustenacular cells

- produce testicular fluid which acts a transport medium for sperm transport in sperimation- the release of sperm in testicular fluid into the lumen of seminiferous tubules

-produce androgen binding proteins that bind and concentrate testosterone around the spermatogenic cells in the seminiferous tubules

epididymal maturation

Cortical process where spermatozoa acquire motility and fertilization capability as they transit through the epididymis

which male accessory reproductive ducts are referred to as storage sites for sperm and why?

Vasa deferentia- enclosed in spermatic cord (with testicular arteries, pampiniform plexus, and nerves)

-Holds sperm until its ready for transportation out of the urethra

-Connects epididymis to the transportation tube

vasectomy

surgical cut and ligation of both vasa deferentia

what is semen

whitish fluid produced by the male reproductive system that contains sperm and other substances necessary for fertilization

where does semen form?

Semen is produced in the reproductive tract as sperm pass through and mix with these fluids during ejaculation.

ejaculatory ducts

during ejaculation, receive sperm from vasa deferentia and secretions from the seminal vesicles and the prostate gland forming semen

indicate the chemicals in the secretion from the seminal vesicles

secrete 60% of seminal fluid contains...

Fructose, coagulating enzymes, ascorbic acid, prostaglandins

fructose in seminal vesicles

produce energy for locomation

vesiculase in seminal vesicles

for the temporary coagulation of ejactulated semen to protect sperm and to begin the process of capacitation

ascorbic acid in seminal vesicles

vitamin C acts as a reducing agent to protest sperm against oxidation; acts as an antioxidant

prostaglandins in seminal vesicles

facilities sperm movement in the female reproductive tract

indicate the chemicals in the secretion from the prostate gland

secrete 33% of seminal fluid; secretion contains: citrate, fibrinolysin, acid phosphatase

-Increase in the levels of the tumor marker, prostate specific antigen (PSA), is indicative of prostate cancer (malignant)

citrate (prostate gland)

acts as calcium chelator to end semen coagulation

fibrinolysin prostate gland

liquefaction agent that liquefies the coagulated semen

acid phosphatase prostate gland

unique enzyme that activities phospholipid metabolism

Increase in acid phosphatase levels are indicative of growth of the prostate gland- benign prostatic hyperplasia (BPH)

indicate the chemicals in the secretion from the bulbourethral glands

secrete a thick alkaline fluid (the pre-ejaculate) which is immobilized/ destroyed in an acidic environment

Which gland secretes acid phosphatase and what is the significance of rising levels of acid phosphatase in blood?

Prostate gland secretes acid phosphatase.

-unique enzyme that activities phospholipid metabolism

-Increase in acid phosphatase levels are indicative of growth of the prostate gland- benign prostatic hyperplasia (BPH)

-Increase in the levels of the tumor marker, prostate specific antigen (PSA), is indicative of prostate cancer (malignant)

female sex organs

The female primary sex organs= female gonads= ovaries

Ovaries are located inside the body in the pelvic cavity

Oogenesis: process by which female gametes called the ova or eggs

Production of the female sex steroid hormones: estrogens and progesterone

female accessory reproductive structures

vulva

ducts: 2 fallopian tubes, uterus, vagina

2 fallopian tubes

they are connected to the uterus and extend to the ovaries without making direct contact with them

1 uterus

- hollow muscular organs; site of implantation and development of the fetus

-Narrow inferior end, the cervix connects to the vagina below

1 vagina

the inferior accessory reproductive duct that also serves as the female organ of copulation

Discuss three structural differences between the male reproductive structures and the female reproductive structure.

Embryonic development

female= sex organs progenitors remain within the pelvic cavity

males= sex organ progenitors descend out of the pelvic cavity

Organ of copulation

Vagina: the inferior accessory reproductive duct

Penis: not a part of male accessory duct

Gonads location

Females: inside of body

Males: outside of body

Which gonad is surrounded by the tunica vaginalis?

testis

process of oogensis

Process by which the fame gametes called the ova or eggs

primary oocyte

what is made once each oogonium begins the first meiotic division and gets arrested in prophase 1 (diploid).

name the 4 different types of ovarian follicles

primordial follicle, primary follicle, secondary follicle, graafian follicle

primordial follicle

contains a primary oocyte surrounded by a single layer squamous cells; a primary oocyte is oogonium arrested in prophase 1; the primary oocyte is diploid (2n)

primary follicle

contains a primary oocyte surrounded by at least 2 layers of cuboidal/ columnar cells

secondary follicle

secretes the estrogen, contains a primary oocyte surrounded by several layers of columnar/ cuboidal cells called granulosa; fluid-filled cavities called vesicles are present in the granulosa cells; external to the granulosa cells are two layers of theca cells; the theca cell express receptors for the hormone LH

LH role in secondary follicle

-LH stimulates the theca cells to produce 3 androgens: DHEA, androstenedione and testosterone which are converted to the 3 types of estrogens by the enzyme AROMATASE, produced by the granulosa cells

DHEA-> Estriol

Androstenedione-> estrone

testosterone-> estradiol

graafian (dominant) follicle

contains a secondary oocyte ( haploid) arrested in metaphase II) and supported by the cumulus oophorus, surrounded by the zona pellucida, corona radiata granulosa cells and theca cells Graafian follicle also contains a fluid filled

which ovarian follicle secretes the estrogens?

graafian follicle

which ovarian follicle contains a secondary oocyte?

graafian follicle

Discuss difference between the process of oogenesis and the process of spermatogenesis.

DO IT QUESTION 16

describe an ovum

Ovum is the secondary oocyte released during ovulation due to the LH surge

-The LH surge cause the Graafian follicle to rupture which triggered the ovum to be release (known as ovulation)

corona radiata

cells that surround the graafin follicle; outermost layer that surrounds the zona pellucida for nutrient support and protection to the oocyte

zona pellucida

non-cellular, glycoprotein rich extracellular fluid rich cells that surrounds the plasma membrane of the oocyte

where does normal fertilization occur?

ampulla; Ovum released from ovary is claimed by ciliary action creating unidirectional current to sweep ovum into infundibulum-> to the ampulla

ovulation

ovum being released from the ovary

is the zygote haploid or diploid?

diploid since it has female and male chromosomes

morula

- 8-16 blastomeres

-Surrounded by intact zona pellucida

-Compaction: increased cell number (with decreased cell size) closed-packed in a confined space because of the presence of intact the zona pellucida

-Blastomeres are polarized with a basal surface and an apical surface: microvili are present on apical surface

-Secretes growth factors with autocrine/ juxtacrine effects to further stimulate cleavage/ growth

blastocyst

-Composed of 32-64 blastomeres; zona pellucida present

Consists of:

-Trophoblast: a single layer of blastomeres at the rim: microvilli on apical surface

Pluriblast or ICM: aggregate of blastomeres (from all tissues/ organs)

-Blastocyst cavity containing blastocyst fluid

-Produces growth factors and the hCG- luteotrophic factor produced around 9 days post-fertilization to rescue the corpus luteum from regressing into a corpus albicans, a scar tissue that is NOT an adrenal endocrine gland

What conceptus implant?

the endometrium of the uterus, usually in the fundus or posterior wall

where does normal implantation occur?

ampulla of fallopian tube

What is Human Chorionic Gonadotropin (HCG)?

hormone produced by the placenta shortly after implantation, to confirm pregnancy

Why is HCG the basis for the pregnancy test?

-The trophoblast cells of the embryo produce it in the case where fertilization occurs

-Stops menstruations

-Produces estrogen and progesterone

pseudohermaphroditism

the condition in which an individual of one sex has external genitalia superficially resembling those of the other sex

Discuss two different ways a genetic male (XY) may present with a female-like external genitalia;

androgen insensitivity syndrome and 5 alpha reductase deficiency syndrome

androgen insensitivity syndrome

androgen receptor dysfunction

XY karyotype are unable to respond to male sex hormones, resulting in female or ambiguous external genitalia despite having testis

5 alpha reductase deficiency syndrome

-guevedoces means penis at 12; DHT is not produced

-XY with a female like external genitalia

-When puberty hits, the girls voice deepens, mustaches develop, their clitoris grows into a penis and their testes descending

-Girl becomes a boy

Discuss one way a genetic female (XX) may present with a male-like external genitalia

Congenital adrenal hyperplasia

XX female genotype: male external genitalia

Name all the organs of the gastrointestinal (GI) system

Gastrointestinal tube and digestive accessory organs

- Oral cavity, pharynx, esophagus, stomach, small intestine, duodenum, large intestine, anus

Name and discuss the functions of three accessory digestive organs associated with the oral cavity

Oral cavity- the mouth/first part of the digestive tract

Teeth- for mastication of food

Mastification- breakdown of food into mush

Salivary glands- moistens food, food molecules into solution to allow taste, forms bolus for swallowing, cleanse oral cavity

Bolus- mixture of masticated food mixture with alivia

Tongue- manipulates the masticated food mixture with saliva from the bolus

name and give the specific function of the 4 types of teeth

8 incisors: for biting into food

4 canines: for tearing

8 premolars: for grinding and crushing

12 molars: for grinding and crushing

give the composition of saliva

-Water: 99%

-Amylase: first step of chemical digestion

-Lysozyme: antimicrobial

explain why chronic dry mouth casues halitosis

reduced saliva allows odor-causing bacteria to thrive. Lack of water and amylase to assist with chemical digestion

where does carbohydrate begin?

It begins in the mouth/ oral cavity as the amylase in saliva starts to break it down during chemical digestion

name phases of deglutition

the oral phase, pharyngeal phase and oesophageal phase

oral phase of deglutition

(voluntary)- bolus of food is pushed by tongue against hard palate and the moves toward the oropharynx

pharyngeal phase

(involuntary)- as bolus moves into oropharynx, the soft palate closes off nasopharynx, the epiglottis closes over laryngeal opening

oesophageal phase

(involuntary)- esophageal muscle contractions push bolus toward stomach; soft palate and epiglottis return to their pre-swallowing positions

Name the 2 parts of the pharynx involved in deglutition.

oropharynx and nasopharynx

This mechanism is a rapid, protective reflex ensuring food enters the esophagus, not the airway. It is accomplished by switching from breathing to swallowing

Common passageway for air and food - swallowed substances have the right of way (as the uvula closes off the nasopharynx and the epiglottis closes off the laryngeal inlet)

"Swallowed substances have the right of way over airflow" - discuss how this is accomplished

○ 1) Soft palate rises

■ Closes off the nasopharynx

■ Prevents food from going up into the nasal cavity

○ 2) Larynx elevates

■ The voice box moves upward

■ Helps position the airway for protection

○ 3) Epiglottis folds down

■ Covers the opening of the larynx (glottis)

■ Prevents food/liquid from entering the trachea

○ 4) Vocal cords close

■ Add an extra seal over the airway

○ 5) Breathing briefly stops (deglutition apnea)

■ Ensures no air is moving while swallowing

○ 6) Upper esophageal sphincter opens

■ Allows food to pass into the esophagus