152 final Flashcards
hormonal regulation in males
hypothalamus releases GnRH, anterior pituitary releases FSH (stim sertoli cells to begin spermatogenesis, inhibits further fsh secretion) and LH (stim interstitial cells to release testosterone that maintains secondary sex characteristics, inhibits further LH and GnRH secretion)
stages of spermatogeneis (6)
1) DNA replication (46 to 92)
2) Mitosis (92 to 46 and 46 for identical cells)
3) primary spermatocyte goes through DNA replication (46 to 92)
4) meiosis 1 completes cross over for genetic variance (92 to 46 & 46)
5) secondary spermatocyte completes meiosis 2 (46 & 46 into 23, 23, 23, 23)
6) spermiogenesis (spermies remodeled)
6) spermiation, sperms lose attachment and enter lumen
stages of oogenesis (5)
1) DNA replication (46 to 92)
2) mitosis (92 to 46 (primary oocyte))
3) primary oocyte begins meiosis 1 (46 to 92)
- —————-birth————————-
4) (92 to 46 and polar body), meiosis 1 complete, secondary oocyte retains all cytoplasm
5) meiosis 2 completed AFTER fertilization, ovum contains all cytoplasm and organelles, proteins for many cell divisions without growth (cleavage)
explain the milk let-down reflex
hypothalamus released PRL-RH to anterior pituitary and N/A to posterior pituitary, Apit releases PRL, Ppit releases oxytocin. BOTH contribute to a positive feedback loop
neurons in the hypothalamus produce ______ to regulate anterior pituitary hormones
tropic hormones
what kinds of hormones are water soluble
Amino acids and peptide hormones
what kinds of hormones are lipid soluble
sterioid hormones (oid, one, T4/T3)
3 ways endocrine gland secretion is stimulated
humoral stimuli (nutrients in blood), hormonal stimuli (in response to other hormones), and neural stimuli (hypothalamus stimulates the release of E/NE, ADH, OT0
parallel muscles
largest change in length. eg- biceps brachii
convergent muscles
vary direction of pull. eg- pectoralis major
pennate muscles
can produce a lot of tension. eg- unipennate = extensor digitorum, bipennate = rectus femoris, multipennate = deltoid
circular muscles
control opening/closing of body
mitochondria
provide ATP for contraction/relaxation
multiple nuclei
pushed to edge of cell
sarcoplasmic reticulum
has Ca pumps
sarcolemma
muscle cell membrane
muscle shortens
isotonic, concentric contraction
muscle lengthens
isotonic, eccentric contraction
muscle stays at same length
isometric contraction
factors affecting strength of whole muscle contraction
frequency of stimulation
number of muscle fibers contracting
type of muscle fiber
slow oxidative fibers
slow contract, slow fatigue. maintains low intensity contractions, aerobic
intermeddiate
aerobic, interediate resistance to muscle fatigue
fast glycolytic
fast contract fast fatigue. anaerobic
purpose of oxygen debt
restore levels of ATP, glycogen, remove lactic acid
circumferential lamellae
layers of bone matrix that wrap around osteons
interstitial lamellae
layers of bone matrix that fills the gaps between osteons
3 functions of trabeculae
withstand stress from different directions
reduce weight
protect red marrow where blood cells are formed
appositiional growth
- osteoclasts in endosteum remove bone matrix in medullary cavity
- osteoblasts in periosteum add bone in circumferential lamellae
- circumferential lamellae remodelled into osteons
3 ways sound waves are characterized
pitch, intensity, timbre
