Chapter 2- Reproduction Flashcards
G0 stage
cell living and serving its purpose and serving its function, without any preparation for division
p53
main protein in control of making sure the DNA is not damaged at checkpoints G1/S and G2/M
Cyclins and cyclin-dependent kinases (CDK)
responsible for the cell cycle. cyclins bind to CDKs creating an activated complex which will phosphorylate transcription factors allowing gene transcription to occur.
hemizygous
males b/c they only have one X-chromosome, so if that X has a disease on it then they are likely to express that disease.
notable gene on Y-chromosome
SRY (sex-determining region Y). initiates testis differentiation and thus the formation of male gonads.
seminiferous tubules
produces sperm that are nourished by the sertoli cells.
2 functional components of the testes
- seminiferous tubules
2. interstitial cells (leydig)
cells of leydig
secrete testosterone and androgens
scrotum
location of testes. temperature 2-4degrees lower than body temp for optimal sperm production.
pathway of sperm through male reproductive system
SEVE(N) UP. Seminiferous tubules, epididymis, vas deferens, ejaculatory duct, NOTHING, urethra, penis
epididymis
sperms flagella gain motility (stored here until ejaculation)
three parts that help with seminal survival and what they do
- seminal vesicles- contribute fructose to nourish sperm
- prostate gland- fluid mildly alkaline properties so sperm can survive in acidic vagina
- bulbourethral (Cowper’s) gland- produce a clear viscous fluid that cleans urethra during sexual arousal
spermatogonia
diploid stem cells (probably going to turn into gametic cells)
mid(connecting) piece of sperm
makes ATP, connects head to tail of sperm (filled with mitochondria)
acrosome
covers head of sperm, derived from golgi apparatus, necessary to penetrate ovum
female gonads
ovaries (produce estrogen and progesterone)
first menstrual cycle
menarche
which stage are primary oocytes frozen in until they continue the cycle during a womans period
prophase 1
which stage are secondary oocytes frozen in until fertilization occurs
metaphase II
2 layers surrounding oocytes
- zona pellucida- surrounds oocyte and is an acellular mixture of glycoproteins that protect oocyte and contain compounds necessary for sperm cell binding
- corona radiata- lies outside (1) and is a layer of cells that adhered to oocyte during ovulation
hypothalamus and reproduction ability
at puberty the hypothalamus allows the production of gonadotropin-releasing hormone (GnRH).
becoming fertile at puberty (both sexes)
GnRH is produced by hypothalamus triggering anterior pituitary to synthesize and release follicle-stimulating hormone (FSH) and luteinizing hormone (LH). these trigger production of other sex hormones that develop and maintain the reproductive system.
amenorrhea
failure to menstruate
estrogen
(ESTABLISHES ENDOMETRIUM) secreted in response to FSH. result in development/maintenance of female reproductive system and female secondary sexual characteristics. stimulate development of reproductive tract in embryo. thickens lining of uterus (endometrium) each month
progesterone
(PROTECTS ENDOMETRIUM) secreted by corpus luteum- remnant follicle that remains after ovulation- in response to LH. development and maintenance of endometrium. IN PREGNANCY: progesterone is supplied by placenta and corpus luteum atrophies and ceases to function.
4 phases of menstrual cycle
- follicular phase (menstrual flow)
- ovulation
- luteal phase
- menstruation
what does a surge in LH do?
induces ovulation (release of the ovum from the ovary into the abdominal- peritoneal- cavity
human chorionic gonadotropin (hCG)
after a zygote forms it develops into a blastocyst that will implant in uterine lining and secrete hCG
corpus luteum
formed from ruptured follicle and secretes estrogen and progesterone to build up uterine lining in preparation for implantation (LH and FSH are inhibited)
sequence of development of mature sperm cell
spermatogonium, primary/secondary spermocyte, spermatid, spermatozoan
what happens during ovulation?
the oocyte is released into the abdominal cavity after the ruptured ovarian follicle pushes it there
seminal vesicles
produce alkaline fructose containing secretions
epididymis
site of sperm maturation
vas deferens
tube connecting epididymis to ejaculatory duct. also surroded by muscle to raise and lower the testes
cowpers gland
produce a fluid to clear traces of urine in the urethra
nondisjunction
incorrect segregation of homologous chromosomes during anaphase I (or of sister chromatids duirng anaphase II)– so one daugher cell has two copies of related genetic material and the other has none.
during which phase does progesterone peak?
luteal phase (supports the endometrium for potential implantation of a blastua) –withdrawal of progesterone causes menses
what do high levels of progesterone and estrogen do during pregnancy
inhibit GnRH secretion, thus preventing FSH and LH secretion and the onset of a new menstrual cycle
