FInal Exam Flashcards
Endocrine and Reproductive
Gametes (sperm and egg) are formed by
testis and ovaries
Fertilization produces one cell ______ with one set of chromosomes from each parent
Zygotes
Gonads produce ____ and secrete
gametes and secrete sex hormones
List the different structures in the male reproductive system
- Testis: sperm formation
- Epidiymis: sperm maturation
- Vas (ductus) deferens: sperm duct
- Seminal vesicle: semen
- Prostate: prostatic fluid; semen
- Urethra: urine
- Scrotum: cools testis
- Penis
______ is a sac of loose skin, fascia and SM divided into two pouches by a septum. It is involved in temperature regulation of the testes
Scrotum
- sperm survive: 2-3o lower temp than core body temp
- Muscle: elevates testes on exposure to cold and arousal
______ are paired, oval glands measuring 2in by 1 inch. They are surrounded by a dense white capsule
Testes
- Septa: 200-300 compartments (lobules)
- Lobules: filled with 2 or 3 semniferous tubules (sperm formation)
Inside the testis are specific cells located either between the lobules, or inside the semniferous tubules (within lobules). What are these cells?
- Leydog: Cells in interstitial space between lobules (testosterone);
- Sertoli: inside the semniferous tubules (in lobules)
Semniferous tubules contain
- sperm forming cells
- Sertoli (supporting cells)
- Interstitial cells in between tubules secrete testosterone
Sertoli cells extend from the basement membrane to the lumen inside Semnifrerous tubules. What are the functions of these cells?
- Androgen binding protein
- -bind testosterone (Leydig cells)
- -influences dev. of male gonads - Inhibin (slow sperm production)
- dec. testosterone - blood-testis barrier
- supports developing sperm
- secrete fluid and controls sperm release /movement into lumen
Spermatogenesis: Sperm forming cells go through 2 meiotic divisions. Describe the steps
- Mitosis
- spermatogonium (2n) - Primary spermatocyte (2n)
- Meiosis I
- 2 secondary spermatocytes (1n) - Meiosis II
- 4 spermatids
- 1n - Sperm
Sperm are adapted for reaching and fertilizing the egg. Describe sperm morphology
- Head:
- -DNA, nucleus, acrosomes with enzymes - Midpiece: mitochondria
- Tail: flagella
* final maturation: epidiymus; regulated by testosterone
Describe hormonal control of male physiology
- GnRH (Hypothalamus)
- FSH and LH (Ant. pit.)
- FSH – Sertoli cells secrete androgen binding protein and inhibin
- -conversion of cholesterol to pregnenolone - LH – Leydig (interstitial) to secrete testosterone
* ABP and testosterone inc. spermatogenesis
* Regulation: Neg. feedback by inc. testosterone and inhibin
There are three main exocrine glands in the male reproductive system: Seminal vesicles, Prostate, and Cowper’s glands (bulbourethral).
Describe seminal vesicles
60% of clear, alkaline seminal fluid
major secretions fructose (nutrition) and prostaglandins (passage of semen)
There are three main exocrine glands in the male reproductive system: Seminal vesicles, Prostate, and Cowper’s glands (bulbourethral).
Describe prostate gland secretions
30% of milky, slightly acidic
*antibiotics
Semen: fibrinogen, fibrinolysin
Semen is a mixture of
fluid + seminal fluid
Normal sperm count: 50 to 150 million/mL
Erection is sexual stimulation caused by _______ nervous system
*point n shoot
Parasympathetic
- arterioles dilate: supply arterioles
- blood enters penis - compress veinous outflow
- blood sinuses of penis engorge with blood
Emission is the next step following erection. It stops at the ejaculatory duct (before ejaculation).
During emission, Muscle contractions ____ the sphincter at the base of the bladder.
Fluids are propelled through the ____, _____ and _____ to the bulb of the penis
Muscle contractions: close sphincter
Fluids propelled: ductus deferens, seminal vesicle and ejaculatory ducts into bulb
Prostatic fluid: secreted into urethra
*controlled by sympathetic
EJaculation is the final step in male sex reflex. Ejaculation is controlled by ______ nervous system.
Sympathetic
-skeletal muscle (bulbospong…) squeeze semen out through urethra
Erectile dysfunction
unable to have an erection
-viagra (vasodilator)
Determine between genetic sex, gonadal sex and phenotypic sex
- Genetic sex: determine by sperm (XX, XY)
- Gonadal sex: testis vs. ovary
Males: testis determining factor - Sertoli and Leydig cells produce anti-mullerian hormone and testosterone (respectively)
Females: absence of testis determining, anti-mullerian and testosterone forms female
- Phenotypic sex: gential tract, external genitalia
List the external parts of the female reproductive system
Externa:
- Vulva:
- pubis
- labia majora
- labia minora
- clitoris - Vestibule
- urethral opening
List the internal reproductive structures in females
Internal:
- Ovaries: egg (oocyte) production and hormones
- Uterine tubes: transport eggs
- uterus: fetal development
- Vagina (birth canal)
- External genitalia (vulva)
- Mammary glands: milk
True/False: Before birth females already produce oogonia
True
Puberty: 400,000
Geriatric/Menopause: death
List the steps of sperm development
- germ cell
- spermatogonium
DNA replication/S phase - Primary spermatocyte
Meiosis I - Secondary spermatocyte
Meiosis II - Spermatid
Spermiogenesis (lose cytosplasm, gain flagella, acrosome) - Spermatozoa
capacitation - increase motility, change in cell surface proteins and acrosome
List the steps in gestation
1. germ cell gestation 2. Oogonium S phase/DNA rep. 3. Primary oocyte meiosis I meiotic arrest until LH, FSH surge at puberty 4. Secondary oocyte + 1 polar body (may degenerate) Meiosis II Meiosis II arrest until fertilization 5. Ovum + up to 3 polar bodies
List the steps in gestation
- germ cell
gestation - Oogonium
S phase/DNA rep.
(Mitosis) - Primary oocyte
meiosis I
meiotic arrest until LH, FSH surge at puberty - Secondary oocyte + 1 polar body (may degenerate)
Meiosis II (metaphase II)
Meiosis II arrest until fertilization - Ovum (graafian follicle) + up to 3 polar bodies
* longest stage between prophase I and metaphase II
* eggs contained in follicles
FSH acts mainly on
granulosa cells
-aromatase: converts androgens from theca to estrogen
granulosa cells (inner) and theca (outer) cells surround the oocyte and secrete mainly
estrogen
- growth/repair of uterine lining
- regulate female cycle
- sex characteristics
- maintain bone and muscle
A mature, graafian follicle reases an oocyte each month during
ovulation
Oocytes develop within
follicles
List the stages of follicular development
- Primordial follicle: single layer of sq. cells around oocyte
- Primary follicle:
- layers of cuboidal granulosa cells around oocyte
- -secrete estrogens - Secondary follicle
- antral cavity forms
- granulosa cells
- theca cells - Graafian follicle
- follicle mature
- ready to ovulate oocyte
* *antrum
* *theca and granulosa - Ovulation
- follicle ruptures releasing oocyte
After ovulation, the empty follicle becomes the Corpus luteum secretes:
- Progesterone – completes the preparation of uterine lining
- Estrogens – work with progesterone
- Relaxin – relaxes uterine muscles and pubic symphysis
- Inhibin – decreases secretion of FSH and LH
When the egg is released, it enters the fimbria end of the fallopian tube.
Describe anatomy of the uterine/fallopian tubes?
-extends from ovary to uterus
- enters infundibulum (fimbraie)
- -cilia sweep - ampulla (central region)
- site of fertilization
- -24 hrs/after ovulation - Isthmus: narrowest portion joins uterus
* zygote reaches uterus about 7 days after ovulation
The female reproductive cycle is controlled by monthly hormonal cycle from the hypothalamus, anterior pituitary and ovary.
List the two cycles
- Ovarian cycle:
- changes in ovary during and after maturation of the follicle and oocyte - Uterine cycle (menstrual)
- prep. uterus to receive fertilized ovum
*if implantation does not occur, functional layer of endometrium is shed during menstruation
- If implantation occurs: continue progesterone
- -zygote release hcG
Non-classical endocrine organs
Heart, Skin
Endocrine system: True/False: Glands that work together to maintain homeostasis
True
______ is a signalling molecule that is released into the bloodstream and modulates an aspect of physiology from a distant location
Hormone
Protein/Peptide hormones
water soluble
- pre-prohormone form in ER
- cleaved to pro-hormone
- cleaved in TGolgi
- hormone packaged into vesicles
ex: oxytocin, all hormones of hypothalamus and ant. pituitary
Steroid hormones
lipid soluble
cholesterl precursor
ex: testosterone, progesterone
- reproductive tract and adrenal cortex
Amine hormones
water soluble
Made from tyrosine
ex: norepinephrine, thyroid
Which two hormones require carrier proteins?
Steroid hormones and thyroid hormone
Hormone effects are mainly due to ____
receptor
3 requirements for hormone receptor:
- high affinity
- high specificity
- signal amplification within the target cell
Types of Hormone receptors
- GPCR (Gs, Gi, Gq)
- Steroid hormone receptors (nucleus)
- Guanylyl cyclase (cGMP)
- Receptor tyrosine kinase (autophosphorylation)
- Tyrosine-kinase associated receptor
(linked to tyrosine kinase that can phosphorylate)
Insulin binds what receptors?
Receptor tyrosine kinase