First Semester Review

Question 1

Meiosis Purpose

Answer 1

to produce gamete/sex cells that combine parental DNA

Question 2

Meiosis I Processes

Answer 2

PMAT; takes a diploid cell, copies the DNA from egg and sperm, separates the homologous chromosome pairs

Question 3

Cell Division Processes Order Mnemonic

Answer 3

P on the MAT: Prophase, Metaphase, Anaphase, Telophase

Question 4

homologous chromosomes

Answer 4

each diploid cell has two sets of chromosomes, homologous chromosomes are a pair of the same chromosome number

Question 5

Meiosis II Processes

Answer 5

PMAT; take a diploid cell and separates the two chromatids of one of the homologous chromosome pairs that was already separated in M1; creates four haploid cells from two diploid cells

Question 6

haploid

Answer 6

only has one chromosome from a homologous chromosome pair

Question 7

diploid

Answer 7

has both chromosomes from a homologous chromosome pair

Question 8

asexual reproduction

Answer 8

uses mitosis to create exact copy of itself; still diploid; no genetic variation through gamete fusion

Question 9

sexual reproduction

Answer 9

requires fertilization of two gametes to produce a zygote that then grows from mitosis and has variant combinations of parent DNA

Question 10

fertilization

Answer 10

the fusion of an egg and a sperm that creates a diploid cell that then goes under meiosis to produce gametes for that organism; that zygote then grows using mitosis

Question 11

chromosomal crossing over in meiosis

Answer 11

during M1: prophase 1 has homologous chromosomes physically attach and then detach and exchange genes so every chromosome is partially egg and partially sperm DNA; contributes to genetic variation

Question 12

Mitosis vs Meiosis

Answer 12

Meiosis: creates 4 genetically variable, haploid cells; produces more gamete cells; Mitosis: creates diploid cells, exact copy of parent, 2 daughter cells

Question 13

Meiosis 1 vs Meiosis 2

Answer 13

M1: splits a homologous chromosome pair to two chromosomes per cell; M2: splits a chromosome into two chromatids

Question 14

Prophase

Answer 14

spindle fibers/microtubules first form and centrioles separate, chromosomes condense

Question 15

Metaphase

Answer 15

nuclear envelope fragments, kinetochore forms on chromosomes, chromosomes align on metaphase plate, microtubules attach to kinetochore

Question 16

Anaphase

Answer 16

cell elongates as mircotubules pull two chromatids (M2 and mitosis)/chromsomes (M1) apart

Question 17

Telophase

Answer 17

fragmented nuclear envelopes reform around new DNA sets, chromosomes uncondense

Question 18

independent assortment in meiosis

Answer 18

random orientation of homologous chromosomes so that during Anaphase 1 a different combination of chromosomes are pulled apart to contribute to genetic variation

Question 19

random fertilization

Answer 19

two gametes meeting to fertilize each other makes infinite possibilities of diploid cells to contribute to genetic variation

Question 20

chiasma

Answer 20

location of chromosomal crossing over where genes swap in homologous chromosomes

Question 21

autosomes

Answer 21

non-sex chromosomes

Question 22

sex determination

Answer 22

if the chromosome set that the sperm contributes has a Y chromosome for the sex chromosome, the organism is male, otherwise it’s female

Question 23

Mitosis purpose

Answer 23

create a new clone cell to renew and repair cells, thus organisms often develop from a single cell

Question 24

prokaryotic genetic material

Answer 24

usually one DNA molecule, circular DNA, floats around in cytoplasm

Question 25

eukaryotic genetic material

Answer 25

packaged into chromosomes, sister chromatids are exact copies, sister chromatids form a homologous chromosome

Question 26

Mitotic interphase

Answer 26

G1: cell grows producing proteins and organelles, S: copies chromosomes, G2: cell grows more, M: cytoplasm and DNA divide

Question 27

cytokenesis: animals vs plants

Answer 27

cytokenesis divides two cells; in animals it creates a cleavage furrow that divides the cytoplasm; in plants, extra vesicles are aligned by microtubules and a new cell wall is created between the cells

Question 28

cell cycle control system

Answer 28

uses checkpoints between each interphase phase (G1, S, G2) to regulate growth, cellular checkpoints are inside and outside of the cell,

Question 29

G0 phase

Answer 29

phase that most cells are in, during interphase where no mitosis is occuring because growth/reproduction is not necessary at the moment

Question 30

cell control system regulators

Answer 30

regulated by proteins and protein complexes: kinase enzymes and cyclin proteins that activate/deactivate proteins; growth factors are proteins that stimulate mitosis

Question 31

cell control system external factors

Answer 31

density-dependent inhibition where crowded cells stop dividing; anchorage dependence: cells need to be attached to something to divide

Question 32

cancerous cells

Answer 32

ignore lack of growth factors, by ignoring growth factors or making own; randomly stop mitosis cycle; can divide forever with nutrients; ignore cell signals to force cell death