Ls 2 Midterm 2

Front 1

Cyclin D-Cdk4

Back 1

acts during middle of G1 - this is restriction point, a key decision point beyond which rest of cell cycle is normally inevitable

Front 2

cyclin E-cdk2

Back 2

acts in middle of G1

Front 3

cyclin A-cdk2

Back 3

acts during S, and also stimulates DNA replication

Front 4

cyclin B-cdk1

Back 4

acts as G2 M boundary, initiating transition to mitosis

Front 5

retinoblastoma protein

Back 5

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

Front 6

prophase

Back 6

forming of spindle (polar microtubles, kinetochore microtubules) and condensing of chromosomes

Front 7

prometaphase

Back 7

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

Front 8

metaphase

Back 8

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

Front 9

spindle checkpoint

Back 9

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

Front 10

anaphase

Back 10

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

Front 11

telophase

Back 11

daughter chromosomes reach poles and telophase passes into next interphase as nuclear evelopes and nucleoli reform and chromatin becomes diffuse

Front 12

cytokinesis

Back 12

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

Front 13

what are two things that are unique about meiosis I?

Back 13

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

Front 14

functions of meiosis

Back 14

reduce chromosome from diploid to haploid, ensure genetic diversity, and make sure they have a full set of chromosomes

Front 15

aneuploidy

Back 15

condition in which one or more chromosomes are either lacking or present in excess

Front 16

what's unique about meiosis II?

Back 16

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

Front 17

differentiation

Back 17

cell function and shape physically defined to cel type

Front 18

determination

Back 18

fate determined to become cell type

Front 19

totipotent

Back 19

can develop into any adult cell

Front 20

unique properties of stem cells

Back 20

can divide many times, undifferentiated, can become many diff specialized cell types

Front 21

pluripotent
multipotent

Back 21

pluripotent can differentiate into anything (found in inner cell mass of blastocyst), multipotent has to be tissue related

Front 22

two major factors that influence cleavage

Back 22

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

Front 23

ectoderm

Back 23

nervous system and epidermis of skin

Front 24

endoderm

Back 24

inner lining of of gut and respiratory system, liver, bladder, pancreas

Front 25

mesoderm

Back 25

skeletal system, muscle and circulatory system, kidneys, gonads, blood cells

Front 26

determination determined by:

Back 26

cytoplasmic segregation and embryonic induction, where interactions with other cells causes determination

Front 27

hypothalamus

Back 27

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

Front 28

anterior pituitary

Back 28

tropic hormones - thyrotropin, adrenocorticotropin, luteinizing hormone, follicle stimulating hormone, as well as growth hormone, prolactin, melanocyte-stimulating hormone, and endorphins/enkephalins

Front 29

posterior pituitary

Back 29

oxytocin, vasopressin

Front 30

thyroid

Back 30

thryoxine (due to thyrotropin) and calcitonin

Front 31

parathyroid hormone

Back 31

protein, produced in parathyroids to resorb bone and raise blood calcium in bones

Front 32

thymosins

Back 32

acts on white blood cells (peptides) to activate immune responses of T cells in lymphatic cells, produced in thymus

Front 33

pancreas

Back 33

insulin, glucagon, somatostatin

Front 34

adrenal medulla

Back 34

epinephrine, norepinephrine

Front 35

adrenal cortex

Back 35

glucocorticoids and mineralocorticoids (aldosterone)

Front 36

thyrotropin

Back 36

tropic hormone, produced in anterior pituitary, in thyroid gland it stimulates synthesis and secretion of thyroxine

Front 37

adrenocorticotropin

Back 37

in adrenal cortex, stimulates release of hormones like epinephrine, noepinephrine, tropic hormone produced in anterior pituitary

Front 38

LH

Back 38

in gonads, stimulates secretion of sex hormones from ovaries, testes, tropic hormone produced in anterior pituitary

Front 39

FSH

Back 39

in gonads, tropic hormone produced in anterior pituitary that stimulates growth and maturation of eggs in females, stimulates sperm production in males

Front 40

growth hormone

Back 40

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

Front 41

prolactin

Back 41

produced in AP, stimulates milk production in mammary glands

Front 42

melanocyte stimulating hormone

Back 42

in melanocytes it controls pigment production, produced in AP

Front 43

endorphins/enkephalins

Back 43

in spinal cord neurons, natural opiates, direct hormone produced in AP

Front 44

oxytocin

Back 44

produced in PP, targets uterus and breasts by causing milk flow and induces birth by stimulating labor contractions

Front 45

ADH/vasopressin

Back 45

in kidneys, stimulates water reabsorption and raises blood pressure, produced in PP

Front 46

thyroxine

Back 46

stimulates and maintains metabolism necessary for normal development, produced in thyroid gland, targets many tissues

Front 47

calcitonin

Back 47

in bone, stimulates bone formation and lowers blood calcium, produced in thyroid gland

Front 48

insulin

Back 48

produced in pancreas, stimulates uptake/metabolism of glucose, increase conversion of glucose to glycogen and fat

Front 49

glucagon

Back 49

in liver, stimulates breakdown of glycogen and raises blood sugar, produced in pancreas

Front 50

somatostatin

Back 50

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)

Front 51

epinephrine, norepinephrine

Back 51

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

Front 52

glucocorticoids (cortisol)

Back 52

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)

Front 53

mineralocorticoids (aldosterone)

Back 53

targets kidneys and stimulates excretion of potassium ions and reabsorption of sodium ions

Front 54

estrogen

Back 54

in breats, uterus, other tissues importnat to stimulate development and maintenance of female characteristics and sexual behavior

Front 55

progesterone

Back 55

in uterus, sustains pregnancy, helps maintain secondary female sexual characteristics

Front 56

mammalian respiratory system : functions

Back 56

eliminate CO2, provide O2
regulate level of blood pH
produce sounds
help to defend body against microbes

Front 57

tidal breathing

Back 57

lungs are dead end sacks, breathing comes in, flows out in same route

Front 58

advantages of closed circulatory systems 1

Back 58

blood flows more rapidly through vessels than through intercellular spaces, transporting nutrients and wastes to and from tissues more rapidly

Front 59

advantages of closed circulatory systems 2

Back 59

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

Front 60

advantages of closed circulatory systems 3

Back 60

by changing resistance in vessels, close dsystems can be more selective in directling blood to specific tissues