Bio 305: Reproduction

Only system not participating in homeostasis

reproductive

Primary reproductive Organs

Gonads (testies, ovaries)

-Produce reproductive calls (gameostais = gametes (sperm +egg)

-secrete sex hormones

accessory reproductive organs

ducts, glands, and external genitalia

DNA: _____ chromosomes, ____ homologous pairs

46;23 (1 is sex chromosome)

Cells divide by _________, during most life of the life cycle

mitosis

Cell division for reproduction

meiosis

Reduction Division

Chromosomes reduced from 46 (diploid, 2n) to 23 (haploid, n)

Two successful divisions to form gametes

meiosis 1 and meiosis 2

crossing over

the exchange of genes between homologous chromosomes, resulting in a mixture of parental characteristics in offspring.

3 hormone chain of command controls reproduction

Hypothalamus - Anterior Pituitary - Gonads

FSH (follicle stimulating hormone)

Secreted by the anterior pituitary and stimulates the gonads to produce sperm and egg.

LH

Causes the production of corpus lutium to produce sex hormones

path of spermatozoa

Tubules - rete testis - epidiymis - efferent ductules - vas deferens

Semi vesicles

-fructose

-Prostaglandins

alkaline fluid

Produced in the prostate gland; Neutralizes acids produced by the prostate gland and vagina

Why do sperm and urine never mix

sphincter in the urea

bulbourethral glands

the two glands below the prostate that secrete a sticky fluid that becomes a component of semen, helps with lubricating

Single ejaculate is about ______- _____ ml

3-6 ; 200-400 million sperm

Spermiogenesis

generate haploid gametes capable of fertilizing eggs

Process to go from Spermatogonia to Primary spermatocyte

Mitosis

Primary spermatocytes to Secondary

Meiosis 1

Secondary spermatocytes to Spermatids

meiosis 2

Spermatids to spermatozoa

Differentiation

Sperm develop from the ______ _____

outside- in

Sertoli cells

support sperm development in tight junctions between each cell to create blood testis barrier

anatomy of sperm

head, midpiece, flagellum

Flagellum aids in _____ of sperm

motility

acrosome of sperm

carries the enzymes that help digest the exterior coats of the egg. At the head of the sperm

GnRH

Gonadotropin-releasing hormone from hypothalamus.

Leydig cells

produce testosterone

Hormone control in Males

GnRH - Anterior pituitary- Sertoli or Leydig cells - Inhibin + Testosterone + Stimulate spermatogenesis

What is responsible for maintaining sperm generation at a constant level

negative feedback

Effects of testasterone?

- required for initial and maintaining

-Decreases GnRH

Where does spermiogenesis occur?

seminiferous tubules

Which cells produce testosterone?

Leydig cells

Oogenesis

secretion of sex hormones estrogen and progesterone

anatomy of female reproductive system

Eggs are contained in ______ within the ovary

follicles

Each month about 10-25 eggs __________ _ __________ but only ____ fully matures and ovulates

start to mature; 1

How many eggs are left after puberty

200-400,000

Approx ______ mature eggs are released in a female lifetime

400

Menapause

When menstration ceases. usually occurs between 45-52 years.

Travel path of egg

ovary- ova duct-

Where is the egg fertilized

fallopian tube

myometrium of uterus

the thick wall of the uterus consisting of smooth muscle and connective tissue

endometrium of uterus

inner layer of the uterus, thickens as the month goes one; if egg is fertilized it will remain, if not it will shed

summary of oogenesis

Oogonia - Mitosis Differentiation - Primary oocytes - 1st Meiotic division - Secondary oocytes - 2nd Meiotic division - ovum

1st Meiotic Division in females :

Begins in utero, completed prior to ovulation

2nd meotic division

Happens after fertilization from sperm

theca cells

estrogen-producing cells in a maturing ovarian follicle

granulosa cells

the majority of the cells surrounding an oocyte in a follicle. Granulosa cells secrete estrogen during the follicular phase of the ovarian cycle (before ovulation).

Development of ovarian follicles

primordial follicle, primary follicle, secondary follicle, graafian follicle, ovulation

luteinization

the process by which granulosa and theca cells are transformed into luteal cells

follicular phase

- Uterine Bleeding (Day 1-7)

- Multiple follicles develop (Day 1-7)

-One follicles becomes dominant (7)

- Dominant follicle mature (estrogen is produced) (7-14)

-Inhibin is produced by granulose cells (7-14)

luteal phase

-End of Ovulation (14)

- Corpus luteum functions (Day 14-25)

-Corpus luteum degenerates (25-28)

Ovulation is triggered by:

a surge in LH and marks the transition to the luteal phase

Small increases in LH and FSH lead to _________ _________ and an _________ in the synthesis and secretion of ovarian __________

follicular maturation; increase; estrogen

LH surge

triggers ovulation +luteinization of corpus lutetium from remaining cells in the ovary to produce progesterone

Fertilized eggs secrete ______ that keep corpus luteum alive

...

Aromatase

enzyme that converts testosterone to estradiol

What causes the androgens from the theca cells to become estrogen after being converted by the granulosa cells

LH-Theca-Diffusion-Granulosa-Estrogen

dysmenorrhea

pain caused by uterine cramps during a menstrual period

fertilized egg is called

zygote

optimal site for fertilization

Ampulla of the oviduct

Sperm is ___________ _________

Receptor dependent

It takes _________ to break down the egg to allow sperm in

many (ultimately they all help 1 sperm)

Cortical reaction

cortical cells break open and release toxins so no other sperm can survive

The only time a women makes HCG

Pregnancy