Reproduction Flashcards
What are primordial germ cells?
Give rise to gonadal ridge
What are the gonads?
Ovaries & Testes
What is the 23rd chromosome pair known as?
The sex chromosomes
Which is the duct for male?
Mesonephric Wolfian Duct
Which duct is in female?
Paramesonephric Duct
What gene does the Y Chromosome have?
SRY Gene
What does the Sex-Determining Region of Y (SRY) gene do?
Codes for the protein: Testis-determining factor (TDF)
What is the TDF?
Regulates development of testes
What is the function of testosterone?
Development of primary & secondary male characteristics
What is the function of the anti-mullerian hormone (AMH)?
Causes regression of the paramesonephric ducts (female ducts)
Define Mitosis
Diploid cell divides to give rise to two diploid daughter cells
What is a diploid cell?
Cell with 46 chromosomes
What is gametogenesis?
Production of the gametes, egg & sperm
What is spermatogenesis?
Creation of sperm (gametogenesis in the male)
What is a haploid cell?
23 chromosomes per cell
What is the G1 Phase?
Synthesis of proteins. Organelles are duplicated
What is the G0 Phase?
After G1, some cells stop dividing (G0)
What is the S phase?
DNA Replication
What is the G2 Phase?
Cell growth & enzyme production
What does spermatogenesis give rise to?
A single diploid cell into 4 haploid spermatozoa
What does oogenesis give rise to?
1 Haploid oocyte & 3 Polar Bodies
When does oogenesis start & stop?
START: Fetus, & puberty
STOP: First Meiotic Arrest, Second Meiotic Arrest & Menopause
What is the first meiotic division?
of chromosomes for one cell goes from 46 to 23 during this division
What is the second Meiotic Division?
The two haploid cells give rise to two more haploid cells (4 sperm)
What is synapsis?
Pairing up of homologues (Chromosome I from dad lines up next to Chromosome I from mom)
What is cross over?
Dad’s genes trade with mom’s chromosomes & vice versa while they’re paired (mixes it up the traits)
What is the function of metaphase I?
Homologous pairs line up next to each other on metaphasal plate
What is a dyad?
Two chromatids attached at the centromere
What happens during Prophase II?
Same thing
What happens during metaphase II?
Centromeres line up on metaphasal plate
What happens in anaphase II?
Centromeres release. Chromatids separate (NOW are called chromosomes)
How much days does spermatogenesis take?
70-75
What is spermatocytogenesis?
Development of spermatogonia
What is spermeogenesis?
Differentiation of spermatids to haploid spermatozoa
What is spermiation?
Release of sperm into seminiferous tubules
What is spermatozoan?
Mature sperm
What is the acrosome?
Apart of the head. Has Hydrolytic/proteolytic enzymes
Eats its way into oocyte
What is the nucleus of the sperm?
Has DNA (23 Chromosomes)
Describe the midpiece of the sperm.
Has mitochondria around tail (makes ATP)
Describe the tail of the sperm
Flagella
What is the function of the testes?
Makes sperm
What is the function of the seminiferous tubules?
Tubules in the testes where sperm is made
What is the sertoli cells?
Surround & maintain developing sperm
What is the function of the sertoli cells?
Makes up the blood-testes barrier
What happens if the blood testes-barrier is compromised?
Immune system will attack sperm & kill it making it sterile
What are leydig cells (interstitial)
Found in the CT outside of seminiferous tubules
What is the function of the leydig cells?
Makes testosterone & androgens (male hormones)
What is the function of accessory sex glands?
Make semen
Describe seminal vesicles
Makes 60% of semen
Describe prostate gland
Makes most of the semen
Describe bulbourethral gland
Makes lubricant
What is semen made out of?
F
How much of an ejaculate is actual sperm?
2-5% are actual sperm cells. The rest is semen
Function of Gonadotropic Releasing Hormone (GnRH)
Releases gonadotropins (FSH & LH) from ant. Pituitary gland
Function of LH
Causes leydig cells to make testosterone
Function of FSH
Makes sperm more sensitive to testosterone
Stimulates spermatogenesis
Function of testosterone
Also triggers spermatogenesis
Function of dartos muscle
Muscle walls of scrotum: Contracts to produce heat when cold & relaxes to release heat when hot
What is the glans of the penis?
Head of penis
What is the prepuce of the penis?
Foreskin