Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key

image

Play button

image

Play button

image

Progress

1/60

Click to flip

60 Cards in this Set

  • Front
  • Back
Cyclin D-Cdk4
acts during middle of G1 - this is restriction point, a key decision point beyond which rest of cell cycle is normally inevitable
cyclin E-cdk2
acts in middle of G1
cyclin A-cdk2
acts during S, and also stimulates DNA replication
cyclin B-cdk1
acts as G2 M boundary, initiating transition to mitosis
retinoblastoma protein
normally inhibits cell cycle but when phosphorylated, no longer blocks restriction point, and cell progresses past G1 into S phase- catalyzed by cdk4 and cdk2
prophase
forming of spindle (polar microtubles, kinetochore microtubules) and condensing of chromosomes
prometaphase
markedby disappearance of nuclear envelope; material of envelope remains in cytoplasm to be reassembled when daughter nuclei reform; chromosomes begin to move towards poles, but movement counteracted by two factors: repulsive force from poles push chrommosomes toward middle region/equatorial plate and chromatids held together at centromere by cohesis
metaphase
centromeres aligned at plate of cell's equator; separation at end of metaphase occurs because cohesis hydrolyzed by protease, called separase; only works because inhibitory subunit securin becomes hydrolyzed after chromatids connected to spindle
spindle checkpoint
how chromosome alignment connected to chromatid spearation (since hydrolyzation of securin only occurs after chromatids connected to spindle, which then enables separase to hydrolyze cohesin). senses whether there are kinetochores unattached to spindle; if happens, securin breakdown blocked and sister chromatids stay together
anaphase
separation of chromatids, as new daughter chromosomes move towards poles; kinetochores, cytoplasmic dynein, have ability to hydrolyze ATP to ADP and phosphate, releasing energy to move chromsomes along microtubules toward poles = 75% of motion, 25% occurs because kinetochore microtubules shorten from poles, drawing chromosomes toward them
telophase
daughter chromosomes reach poles and telophase passes into next interphase as nuclear evelopes and nucleoli reform and chromatin becomes diffuse
cytokinesis
usually followed after mitosis, it is division of cell's cytoplasm; animal cells divide by furrowing plasma membrane, with help of actin adn myosin; in plant cells, membranous vesicles, with help from microtubules and kinesin, form new plasma membrane and contribute contents to cell plate = cell wall
what are two things that are unique about meiosis I?
first is that homologous chromosomes pair along their entire lengths; after metaphase 1, homologous chromosomes separate; indiivdual chromosomes, each consisting of two sister chromatids, remain intact until end of metaphase II in second meiotic division
functions of meiosis
reduce chromosome from diploid to haploid, ensure genetic diversity, and make sure they have a full set of chromosomes
aneuploidy
condition in which one or more chromosomes are either lacking or present in excess
what's unique about meiosis II?
no DNA replication, has two chromatids that differ from each other with crossing over, and there is haploid number of chromosomes lining up on plate
differentiation
cell function and shape physically defined to cel type
determination
fate determined to become cell type
totipotent
can develop into any adult cell
unique properties of stem cells
can divide many times, undifferentiated, can become many diff specialized cell types
pluripotent
multipotent
pluripotent can differentiate into anything (found in inner cell mass of blastocyst), multipotent has to be tissue related
two major factors that influence cleavage
yolk- influences pattern of cell diision by impeding pinching in plasma membrane to form cleavage furrow between daughter cells
cytoplasmic determiantns stored in egg guide formation of mitotic spindles and timing of cell divisions
ectoderm
nervous system and epidermis of skin
endoderm
inner lining of of gut and respiratory system, liver, bladder, pancreas
mesoderm
skeletal system, muscle and circulatory system, kidneys, gonads, blood cells
determination determined by:
cytoplasmic segregation and embryonic induction, where interactions with other cells causes determination
hypothalamus
sends tropic releasing hormones and release-inhibiting hormones (neurohormones), which control secretion of hormones of anterior pituitary, and releases oxytocin and antidiuretic hormone/vasopressin through posterior pituitary
anterior pituitary
tropic hormones - thyrotropin, adrenocorticotropin, luteinizing hormone, follicle stimulating hormone, as well as growth hormone, prolactin, melanocyte-stimulating hormone, and endorphins/enkephalins
posterior pituitary
oxytocin, vasopressin
thyroid
thryoxine (due to thyrotropin) and calcitonin
parathyroid hormone
protein, produced in parathyroids to resorb bone and raise blood calcium in bones
thymosins
acts on white blood cells (peptides) to activate immune responses of T cells in lymphatic cells, produced in thymus
pancreas
insulin, glucagon, somatostatin
adrenal medulla
epinephrine, norepinephrine
adrenal cortex
glucocorticoids and mineralocorticoids (aldosterone)
thyrotropin
tropic hormone, produced in anterior pituitary, in thyroid gland it stimulates synthesis and secretion of thyroxine
adrenocorticotropin
in adrenal cortex, stimulates release of hormones like epinephrine, noepinephrine, tropic hormone produced in anterior pituitary
LH
in gonads, stimulates secretion of sex hormones from ovaries, testes, tropic hormone produced in anterior pituitary
FSH
in gonads, tropic hormone produced in anterior pituitary that stimulates growth and maturation of eggs in females, stimulates sperm production in males
growth hormone
in bone, liver, muscles, stimulates protein synthesis and growth - direct hormone produced by AP (stimulates cells to take up AA for protein synthesis, also stimulates liver cells to produce somatomedins which stimulate bone/cartilage growth
prolactin
produced in AP, stimulates milk production in mammary glands
melanocyte stimulating hormone
in melanocytes it controls pigment production, produced in AP
endorphins/enkephalins
in spinal cord neurons, natural opiates, direct hormone produced in AP
oxytocin
produced in PP, targets uterus and breasts by causing milk flow and induces birth by stimulating labor contractions
ADH/vasopressin
in kidneys, stimulates water reabsorption and raises blood pressure, produced in PP
thyroxine
stimulates and maintains metabolism necessary for normal development, produced in thyroid gland, targets many tissues
calcitonin
in bone, stimulates bone formation and lowers blood calcium, produced in thyroid gland
insulin
produced in pancreas, stimulates uptake/metabolism of glucose, increase conversion of glucose to glycogen and fat
glucagon
in liver, stimulates breakdown of glycogen and raises blood sugar, produced in pancreas
somatostatin
in digestive tract and pancreas, inhibits insulin and glucagon release, decreases secretion, motility, absorption in digestive tract (after it detects that there is a rise in blood glucose level)
epinephrine, norepinephrine
targets heart, blood, vessels, liver, fat cells and stimulates fight or flight reactions, increase heart rate, redistribute blood to muscles and raise blood sugar, produced in adrenal medulla
glucocorticoids (cortisol)
produced in adrenal cortex, mediate response ot stress, reduce metabolism of glucose, increase metabolism of proteins/fats, reduce inflammation and immune response (made from cholesterol)
mineralocorticoids (aldosterone)
targets kidneys and stimulates excretion of potassium ions and reabsorption of sodium ions
estrogen
in breats, uterus, other tissues importnat to stimulate development and maintenance of female characteristics and sexual behavior
progesterone
in uterus, sustains pregnancy, helps maintain secondary female sexual characteristics
mammalian respiratory system : functions
eliminate CO2, provide O2
regulate level of blood pH
produce sounds
help to defend body against microbes
tidal breathing
lungs are dead end sacks, breathing comes in, flows out in same route
advantages of closed circulatory systems 1
blood flows more rapidly through vessels than through intercellular spaces, transporting nutrients and wastes to and from tissues more rapidly
advantages of closed circulatory systems 2
specialized cells and large molecules that aid in transport of hormones and nutrients can be kept within vessels but can drop their cargo in tissues where needed
advantages of closed circulatory systems 3
by changing resistance in vessels, close dsystems can be more selective in directling blood to specific tissues