Reproductive Systems

glans penis

Tissue at the end of the penis that contains most nerve endings

Penis

Male reproductive organ

Foreskin

a covering of skin over the penile glans

Shaft of the penis

Body of the penis

Urethra male

tube from bladder to outside of body also carries semen to outside.

vas deferens valve

Valve that controls whether urine or semen is coming out of the urethra

vas deferens

tube that carries sperm from the epididymis to the urethra

The vas deferens moves sperm using

Peristalsis

Vasectomy

surgical removal of a part of the vas deferens

ejaculatory duct

Where the seminal vesicle and vas deferens connect

Semen and urine leaves a male body through the

urethra and a valve controls whether semen or urine goes out

Erection

Dilation of blood vessels in the penis to make it hard

Cowper gland

Produces anti acid fluid and mucus that clean out the urethra before ejaculation

Prostate gland

secretes alkaline fluid that nourishes and protects sperm as well as neutralizes vaginal acidity

Seminal vesicle

Secretes fluid containing fructose (to nourish sperm) and alkaline fluid

Scrotum

External sac that contains the testes

The testes are kept lower in order to

Keep them cool

Epididymis

where final sperm maturation occurs

Testes

Where sperm production occurs, contains seminiferous tubules

Semen

A thick fluid containing sperm, fructose, anti acid fluid, mucus, alkaline

Male Hormones

testosterone and inhibin

GnRH

Gland: Hypothalamus

Target: Anterior Pituitary

Effect: Makes anterior pituitary secrete hormones

Testosterone

Gland: Testes

Target: testes, muscles, hair follicles

Effect: promotes sperm formation and development of secondary sex characteristics

Inhibin

Gland: Testes

Target: anterior pituitary

Effect: inhibits the release of FSH

primary sexual characteristics (male)

Enlargement of penis and testes, sperm production, all directly relate to reproduction

secondary sexual characteristics (male)

growth, aggression, hair, body odour, voice deepens

Parts of a Sperm

Head- contain nucleus and acrosome which stores enzymes needed to penetrate the egg

Middle piece-contains mitochondria and provides energy

Tail-movement

Interstitial Cells

in the testes, between the seminiferous tubules and produce testosterone

Sertoli cells

cells found within the seminiferous tubules that provide metabolic support for spermatogenesis

seminipherous tubules

in the testes, where spermatogenesis occurs

Spermatogenesis

Formation of sperm

Stages of Spermatogenesis

1. Spermatogonium (2n) goes through mitosis ->

2. Primary spermatocyte (2n) goes through meiosis 1 ->

3. Secondary spermatocyte (n) goes through meiosis 2 ->

4. Spermatids (n) mature in the epididymis

5. Sperm cells

Pathway of the sperm out of the body

testes, epididymis, vas deferens, urethra

vaginal opening

opening of the vagina

cervix

The opening to the uterus, made of muscle

uterus

Female organ of reproduction used to house the developing fetus.

Endometrium

inner lining of the uterus

myometrium

muscle layer of the uterus

oviducts (fallopian tubes)

site of fertilization, connected to the fimbrae

Fimbrae

sweeps the egg of from the ovary into the oviduct

Ovaries

Glands that produce the egg cells and hormones

Estrogen

Gland: Ovaries

Target: uterus, breasts, bone marrow, brain

Effect: stimulates growth of the endometrium and promotes development of secondary sexual characteristics

Progesterone

Gland: Ovaries

Target: uterus

Effect: promotes growth of uterine lining

primary sexual characteristics (female)

ovum development, breast development, mensural cycle

secondary sexual characteristics (female)

hips widen, body hair, body odour, body fat

menstrual cycle and ovarian cycle lasts

28 days

4 phases of menstrual cycle

flow, follicle, ovulation, luteal

Flow Phase

days 0-5 where endometrium is shed (menstrual flow), FSH causes follicle in ovary to stimulate

Ovary follicle

single oocyte and support cells

Hormone levels during the flow phase

low levels of estrogen and progesterone

high levels of FSH

no neg feedback

Follicle Phase

day 6-13 where follicle grows and secretes estrogen

estrogen rebuilds endometrium

During each ovarian cycle only

1 follicle is stimulated

Hormone levels during the follicle phase

increase estrogen

neg feedback from estrogen on ant pit

Ovulation Phase

day 14 where LH surge causes follicle to burst and release egg

Once a follicle bursts it is called a

corpus luteum

Hormone levels during ovulation

high levels of estrogen cause + feedback on ant pit leading to LH surge

Luteal Phase (part 1)

days 15-23 where corpus luteum secretes progesterone causing the endometrium to thicken and vascularize

Hormone levels during luteal phase (part 1)

high levels of progesterone (and estrogen) causing neg feedback on ant pit

Luteal Phase (part 2)

day 24-28 where corpus luteum breaks down into corpus albican and FSH starts to rise again

corpus albicans

broken down corpus luteum

Hormone levels during luteal phase (part 2)

progesterone and estrogen decrease

FSH begins to rise

Without progesterone the endometrium

becomes unstable and sheds (flow phase)

Oogenesis is

Egg production

Ovum

A mature egg cell

Oogenesis creates

1 egg and 3 polar bodies

Fusion of the egg and sperm causes

meiosis 2 to finish in the oocyte

Fertalization occurs in the

oviducts

First Trimester

0-12 weeks, when basic functions are made

Zygote

fertilized egg

Morula

ball of cells formed by cleavage (16-32 cells)

Cleavage

zygote going through mitosis

Blastocyte

hollow ball of cells filled with fluid that embeds in the endometrium

Blastocytes secrete

hCH to maintain corpus luteum

hCG (human chorionic gonadotropin)

This stimulates the corpus luteum to produce estrogen & progesterone, declines once the placenta takes over

gastrula/gastrulation

going from blastocyst to germ layers through differentiation

Germ layers

ectoderm (outer), mesoderm (middle), endoderm (inner)

Extra-embryonic membranes

amnion, chorion, yolk sac, and allantois

Amnion

creates the amniotic sac where the baby develops

Chorion

creates the placenta and secretes hcg

Yolk Sac

forms digestive tract, provides first blood cells

Allantois

create the umbilical cord adn provides blood vessels for the placenta

umbilical cord

a tube containing the blood vessels connecting the fetus and placenta

Embryo

once germ layers are formed

Organgenesis

formation of organs

Neural tube formation (neuralation)

creates the eventual spinal cord and brain from the mesoderm

Fetus

embryo becomes a fetus at 8 weeks

Placenta

organ that nourishes the fetus, made of fetal cells

The placenta acts as a

barrier for substances

Placenta produces

estrogen, progesterone (2-3 months) and relaxin (3rd trimester)

Estrogen develops the

Breasts for lactation

stages of zygote development

Zygote->(Cleavage)->Morula->Blastocyte->(Gastrula)->Germ layers and extra embryonic layers->Embryo->Fetus

Trophoblast

outer layer of blastocyst

inner cell mass of blastocyst is called

embryoblast which turns into the embryo

Ectoderm creates

outer skin and nervous system

Mesoderm creates

muscles, heart, bones, internal reproductive organs ect.

Endoderm creates

Digestive and respiratory systems

Differentiation

process in which cells become specialized in structure and function

Second trimester

Fetus structures develop

Third Trimester

Structures grow and strengthen

Stages of birth

dilation, expulsion, placental