reproductive system

reproductive system

male gamete fertilizes a female gamete to produce an offspring with half the genetic makeup of each parent (ensures genetic variation) and hormones play a key role

where does fertilization occur

in the fallopian tube

follicle cells

cells within ovaries

Corpus luteum

outer ring of the follicle that remains in the ovary that begins to divide and fill in the area left by ovulation and produces progesterone for 10-12 days after ovulation

Spermatozoa

sperm cells that are made in the testis inside the seminiferous tubules

Spermatogonia: diploid

germinal epithelial cells located near the outer wall of the seminiferous tubules (undergoes mitosis or meiosis)

Spermatogonia are diploid and contain 23 homologous pairs (46 chromosomes)

Ovum

largest cell due to the unequal division of the cytoplasm during meiosis to ensure that one cell receives all the cytoplasm, nutrients, and organelles necessary to start a new life

Oogonia: diploid

cells within ovaries that undergo mitosis to build up the numbers of oogonia and grew into larger cells (oocytes) both types of cells are diploid

Polar bodies

3 of the cells that are not used as gametes because they are too small to produce a viable zygote

small haploid cell that is not used

Secondary oocyte

one large haploid cell

ovum

Yolk

contains nutrients

Cortical granules

small vesicles that release contents at fertilization to prevent more than one sperm from entering

located around the interior of the plasma membrane of the ovum

Zona pellucida

layer of glycoproteins outside the plasma membrane to help with sperm binding

Cortical reaction

designed to prevent more than one spermatozoa from fertilizing the ovum (polyspermy)

How is polyspermy avoided at fertilization?

When the sperm and egg membranes fuse, cortical granules release enzymes outside the egg. These enzymes change the zona pellucida so it becomes impermeable, blocking any additional sperm from entering.

Zygote

newly fertilized ovum that is diploid

Implantation

blastocysts embeds itself in the endometrium layer of the uterus

Placenta

forms from the trophoblast layer of the blastocyst and forms from tissue from both the embryo and mother

site of nutrient and gas exchange between the mother and fetus

Umbilical cord

protective sheath that develops and covers three fetal blood vessels

label the male reproductive system

a. Testis

b. Epididymis

c. Scrotum

d. Vas deferens

e. Seminal vesicles

f. Prostate gland

g. Penis

testes

gland that produces sperm and hormone testosterone

Epididymis

location where sperm mature and are capable of swimming by use of their flagella

Scrotum

sacs that hold testes outside the body so sperm production can occur at a temperature cooler than body temperature

Vas deferens

muscular tube that carries mature sperm from epididymis to urethra

Seminal vesicles

small glands that produce and add seminal fluid to the semen

Prostate gland

gland that produces much of the seminal fluid including carbohydrates for the sperm

Penis

organ that fills with blood to facilitate ejaculation of sperm

Ovary

gland that produces and secretes estrogen and ovum (egg)

Fallopian tubes

 ducts that carry the ovum (or early embryo) to the uterus

Uterus

muscular structure where the early embryo implants and develops if a pregnancy occurs

Cervix

lower muscular portion of the uterus which has an opening to the vagina that allows sperm to enter and pathway for childbirth

Vagina

muscular tube that leads from outside of body to cervix, where sperm enters the female reproductive system

State the roles of sex hormones in the development of males and females in an embryo.

• Males: Testosterone promotes development of male reproductive organs.

• Females: Estrogen and progesterone support development of female reproductive organs.

State the roles of sex hormones in the development of male and female characteristics during puberty.

Female secondary characteristics: enlargement of breasts, growth of pubic and underarm hair, and widening of hips.

Male secondary characteristics: growth of facial, underarm, chest, and pubic hair, and enlargement of the larynx which leads to deepening of the voice.

State the types of sex chromosomes that determine male and female.

• Receive x from mom

• Receive either X or Y from father (male determines gender of baby)

XX- female

XY- make

State the four phases of the menstrual cycle

FOLM

follicular phase

ovulation

luteal phase

menstruation

follicular phase

maturing of ovum in follicle

Ovulation

release of egg from follicle

Luteal phase

egg travels down Fallopian tube and fertilization can occur

Menstruation

no fertilization, then the blood vessels of the endometrium lining is broken down and released

State the function of  GnRH and include where is it made and what it targets

made in hypothalamus, targets the anterior pituitary, to produce and secrete two hormones that target the ovaries

• LH

• FSH

State the effects of FSH and LH on the ovaries during the menstrual cycle.

FSH and LH stimulate the ovaries to produce follicles and increase estrogen. Estrogen acts on the uterus to increase blood vessels in the endometrium and also stimulates the pituitary gland to release more FSH and LH in a positive feedback loop. A spike in FSH and especially LH leads to ovulation, which is the release of the oocyte from the Graafian follicle into the Fallopian tube.

 State if estrogen, progesterone, LH, and FSH is high or low at ovulation.

• Estrogen: high

• Progesterone: low

• LH: high

• FSH: high

State the function of estrogen and progesterone during the menstrual cycle

• to increase blood vessels in the uterus

• production of ovum

• negative feedback to hypothalamus

p-

•  maintains the lining of the uterus so the embryo can impant

Explain the process of spermatogenesis

Spermatogenesis is the process where spermatogonia (diploid cells) divide by mitosis and then undergo meiosis. Meiosis I produces two cells, and meiosis II produces four haploid spermatozoa.

Explain the process of oogenesis

Oogenesis is the production of female gametes by meiosis. It involves the division of chromosomes and produces four cells at the end of meiosis. However, three of these cells become polar bodies because they are too small to function as gametes and are not used. Only one large cell becomes the ovum, which is the functional egg cell.

Compare and contrast the spermatozoa and the ovum

spermatozoa

• Flagellum for movement 

• produced in large numbers

• small

ovum

• large

• contains the nutrients needed for early embryonic development

• produced one at a time

List the steps of fertilization

• Sperm reaches egg and attaches

• Acrosome reaction for the sperm to get into the egg 

• Plasma membranes of sperm and egg fuse

• Cortical reaction: chemicals released that blocks all other sperm from entering

• Sperm’s nucleus and egg’s nucleus join to form the zygote

Describe the parts of the blastocyst

Trophoblast: placenta

Inner cell mass: embryo

Fluid filled cavity

State the materials that pass from the mother to the fetus through the umbilical cord from the placenta.

Oxygen and nutrients pass from the mother to the fetus through the placenta and umbilical cord.

State the hormone that is secreted by the embryo to signal the corpus luteum to maintain the endometrium.

HCG

GnRH (hormone chart)

Location made: hypothalamus

Target Location: anterior pituitary

Function: stimulates the anterior pituitary to release FSH and LH

FSH(hormone chart)

Location made: anterior pituitary

Target Location: ovary

Function: stimulates the follicle in the ovary to mature

LH(hormone chart)

Location made: anterior pituitary

Target Location: ovary

Function: triggers ovulation

Estrogen(Hormone chart)

Location made: ovary

Target Location: linning of the uterus, secondary sex characteristics

Function:

• increase blood vessels in uuterus

• negative feedback to hypothalamus

• embryo development of gender

• production of ovum

progesterone

Location made: ovary: corpus luteum

Target Location: lining of the uterus

Function: maintaining the lining of the uterus so the embryo can implant

HCG

Location made: Embryo

Target Location: ovary

Function: enters the mothers blood and maintains the corpus luteum to maintain the uterus lining

testosterons

Location made: testies

Target Location: male secondary sex characteristic cells

Function: produces sperm and secondary sex characteristic cells

acrosome reaction

from sperm

enzymes to break through egg

What is the result of HCG being released by the embryo?

prevents the degeneration of the corpus luteum

what structure produces alkaline fluid and carbohydrates in the male reproductive system?

prostate gland

what are the male germinal epithelial cells that are diploid called?

spermatogonia