EXAM 2 Flashcards

Question

role of mitosis in a cell and chromosome number

Answer 1

chromatin = DNA and protein -humans have 46 chromosomes and 23 pairs diploid: 2 of each type of chromosome present haploid: cells with half (1 of each type of chromosome) 23 CHROM.

Answer 2

sister chromatids separate into daughter chromosomes then are distributed to 2 daughter nuclei

Answer 3

centrosomes move away to opposite ends of nucleus -miotic spindle fibers begin forming -spindle fibers are made of tubulin -DNA condensed into chromosomes -ORGANIZED BY CENTROSOMES

Answer 4

nuclear envelop breaks down -kinetochores hook up to spindle fibers -kinetochores have motor proteins that pull chromosomes along fibers

Answer 5

chromosomes align in center of meta plate -each chromosome has 2 kinetochores (one for each chromatid) -spindle microtubules are on OPPOSITE POLES

Answer 6

centromeres of sister chromatids separate -kentechore drags daughter chromosomes to opposite poles (spindles shorten)

Answer 7

OPPOSITE OF PROPHASE -spindle reduce in size, nuclear envelop reforms -chromosomes uncoil and lengthen

Answer 8

cytoplasm the chromosomes into 2 separate cells

Answer 9

A: centrosomes contain centrioles P: no centrioles meristematic tissue has ability to divide just has centrosome and spindle fibers

Answer 10

A: in telophase, cleavage furrow (indent of membrane between 2 nuclei) forms -forms contractile ring to construct daughter cells -separates cytoplasm P: cell wall prevent furrowing -builds new cell wall between cells (small flat disk) -golgi produces vesicles for cell plate -membrane of vesicles finishes membrane of cells complete= release molecules to form new cell walls

Answer 11

occurs in sexually reproducing organisms -reduces number of chromosomes in half -genetic variation from both parents -begins with 1diploid parent and ends with 4 haploid daughter cells

Answer 12

ARE ALIKE NOT IDENTICAL match in length, centromere position, and gene location -different version of gene found in same locus (1 allel from mom, 1 from dad)

Answer 13

turn to haploid!! prophase: homo. chromosomes come together @ synapsis -each pair with 4 chromatids = tetrad -NON SISTER CHROMATIDS CROSS OVER metaphase: align at meta plate -independent assortment: randomly assemble Anaphase: HC separate and pulled top opposite poles of spindle fibers telophase: daughter cells have 1 chromosome ( next cell divide)

Answer 14

4 daughter cells are produces wuth haploid chromosomes daughter cells are called gametes (egg and sperm fuse) fertilization restores diploid # P: cells have 1 chromosome from each HC pair M: chromosomes align at meta plate A: sis chromatids separate becoming daughter chromosomes and move to opposite poles T: spindle disappear, nucleus forms, cytokinesis

Answer 15

DNA replication takes place prior to both BUT meiosis is 2 nucelar divisions and mitosis is 1 -meiosis= 4 daughter cells while mitosis = 2 daughter cells -meiosis is haploid (not identical), mitosis is diploid (identical)

Answer 16

zygote: diploid cell formed by union of 2 gametes (production of fertilization) mitosis is involved in the growht of a child and repairs tissues

Answer 17

in testes and begins at puberty -primary spermatocytes divide in meiosis then divide again in meiosis 2 to produce 4 spermatids (spermatids mature to sperm)

Answer 18

in fetus, primary oocytes are arrested at P1 resumes at puberty and primary oocyte contains meiosis each menstrual cycle -primary oocyte divides in Meiosis 1, if secondary is fertilized meiosis 2 will proceed -if not it disintegrates

Answer 19

C6H12O6 + 6O2 => 6CO2 + 6H2O produces 36-38 ATP molecules

Answer 20

NAD+: coenzyme in oxidation reductions that accepts electrons and hydro ions to become NADH (carries to ETC) NAD+ cycle: coenye NAD+ accepts hydrogen atoms and NADH results, when NADH passes on electrons, NAD+ results FAD: coenzyme in oxidation reduction that becomes FADH2 (carries electrons to ETC)

Answer 21

glycolysis: outside mitochondria and does not use oxygen citric acid cycle and prep reaction: in matrix, use oxygen, give of CO2 ETC: in cristae, use oxygen

Answer 22

takes place within in the cytoplasm and results in the break of glucose into 2 pyruvate molecules INPUTS: 6 carbon glucose, 2 NAD+, 2ATP, 4ADP, 2 phosphate OUTPUT: 2 (3 CARBON pyruvate), 2NADH, 2ADP, 4 ATP (2 ATP net gain)

Answer 23

2 ATP are used to activate glucose (6C) -results in splitting into 2 (3C) pyruvate with attached phosphate group

Answer 24

1. oxidation of pyruvate occurs by removal of hydrogen atoms -hydro atoms are picked up by NAD+ and NADh results (NADH will later pass thru ETC ) -4 high energy phosphate groups results 2. substrate level ATP synthesis: ATP is formed by transferring phosphate from metabolic substrate to ADP w enzyme 3. oxidation occurs by removal of water 4. substrate level synthesis results in 2 molecules of pyruvate with 2 more ATP made

Answer 25

is o2 is limited, pyruvate molecules accumulate in the cell and intermediates (Nad, Fad) cannot be recycled fermentation: anaerobic breakdon of glucose that results ina gain of 2 ATP and end products

Answer 26

lactic acid and alcohol: helps recycle NAD+ molecules and allows glycolysis to proceed ATP production -fermentation yields only 2 ATP molecules -toxic to cells -release CO2

Answer 27

pyruvate is converted to 2 carbon acetyl group attached to CoA where CO2 is given off -oxidation reaction where hydro atos are removed from pyruvate by NAD+ resulting in NADH (occurs twice) OUTPUT: 2 NADH, 2CO2, 2acetyl coA

Answer 28

TURNS TWICE, MULTIPLY BY 2 -C2 acetyl group w Co A joins with C4 molecules creating a C6 citrate -oxidation produces 2NADH -loss of CO2 = C4 molecule -1ATP produced by substrate level synthesis -additional oxidation = FADH2, NADH, regeneration of OG C4 molecule INPUTS: 2 acetly groups, 6 NAD, 2 FAD, 2ADP + 2P OUTPUT: 4CO2, 6NADH, 2FADH, 2 ATP

Answer 29

series of protein carries that pass electrons form 1 to another -electron carriers are called cytochromes (iron molecules) -NADH and FADH2 arrive carrying high energy electrons (two per carrier) -as electrons are passed from each protein, electron gradient is generated -once gradient reaches a certain level, ATP synthase enzyme uses energy in gradient to re-energize ADP forming ATP -oxygen is used as terminal electron acceptor

Answer 30

autotrophs: photosynthesis carbohydrates, make their own food (plants) heterotrophs: CANNOT synthesize its own food, consumes organic material made by autotrophs Both of them use organic molecules produced by photosynthesis for growth and repair and a source of chemical energy for work

Answer 31

humans and all organsisms release CO2 in the air as a waste product from metabolic pathways such as cellular respiration. Some of the same CO2 is entered into the leaf through the stomata and is converted into carbohydrates Glucose is the main form of energy

Answer 32

6CO2+6H2O ==> C6H12O6 + 6O2

Answer 33

light reactions: captures solar energy, takes place in thylakoid membrane, releases oxygen and provides molecules for Calvin NADP+ carries hydrogen atoms from light to Calvin, when accepted, becomes NADPH Calvin Cycle: in stroma of chloroplasts, uses the products of light reaction to reduce CO2 to a carb ATP CARRIES ENERGY FROM LIGHT TO CALVIN

Answer 34

chlorophylls a and b absorbs violet, indigo, blue, and red light, green light is reflected so we see green carotenoids absorb violet-blue-green range reflecting yellow or orange colors photosynthesis begins when these pigemnts absorb light

Answer 35

electron flow traced from water to NADP+ -2 photosystems which are a pigement complex and electron acceptors within thylakoid membrane -is like an antenna for gathering solar energy

Answer 36

Photosystem 2: pigment complex and electron acceptors, water is split to replace energized electrons and O2 is released, ATP is made ETC: carries electrons from PSII to PS I, uses energy to pump hydro ions from stroma to thylakoid space Photosystem 1: pigemtn complex and electron acceptors, adjacent to enzyme that reduces NADP+ to NADPH ATP synthase complex: has channel for hydro ion flow, and flow drives ATP synthase to join ADP and P

Answer 37

water is an electron donor electron acceptor is NADP+ which turns to NADPH

Answer 38

Thylakoid space acts as a reservoir for hydrogen ions (H+) -H+ from water being split within thylakoid space -pumped in by electron transport chain -More H+ in thylakoid space than stroma Electrochemical gradient H+ can only flow through ATP synthase Energy powers making ATP by chemiosmosis

Answer 39

step 1!! 3 molecules of CO2 are attached to 3 RuBP -results in 3 6-carbon molecules -then splits in half forming 6 3-carbon molecules (1st 3C molecule is 3PG) -attachment of CO2 and RuBP is catalyzed by RuBP carboxylase

Answer 40

step 2!! -using ATP, 3PG changes to BPG -this causes ATP to turn to ADP+P -using NADPH, BPG then becomes G3P -this causes NADPH to become NADP+

Answer 41

step 3!! TAKES 3 TURNS OF CYCLE -5 molecules of G3P become 3 molecules of RuBP -3 molecules of ATP become 3 molecules of ADP + P -remaining G3P is used to make glucose

Answer 42

-can be combined with fructose to form sucrose for transportation of carbs -starting point of synthesis of starch and cellulose (starch is storage of glucose found in chloroplasts and amyloplasts of roots) (cellulose is the structural component of the plant cell and becomes fiber in our diet) -can form fatty acids and glycerol to combine to make plant oils (sunflower, olive oil, corn oil, etc)

Answer 43

photosynthesis products are the reactants for cellular respiration

Answer 44

stroma stomata are small lip openings for CO2

Answer 45

The H+ ions flow through an ATP synthase complex, back into the matrix. As the H+ pass through the complex, energy is released and captured to form ATP from ADP (through ATP synthase complex to make ATP, through channel protein to release it)

Answer 46

tissue in leaves specialized for photosynthesis

Answer 47

glucose comes from CO2, oxygen comes from H2O

Answer 48

watson and crick

Answer 49

synthesize the proper nucleotide to match with the base read on the old strand

Answer 50

exons!! introns intervene

Answer 51

The p53 protein causes the cell to divide even if the DNA is damaged.

Answer 52

each chromosome composed of two sister chromatids at both

Answer 53

homologous chromosomes for meiosis, each chromosome is composed of two sister chromatids for mitosis

Answer 54

Four equal size daughter cells will form.

Answer 55

in order to regenerate NAD+

Answer 56

Through a membrane transport protein.

Answer 57

thylakoid membrane