Honors Bio Chapter 8

Front 1

autosome

Back 1

all chromosomes other than sec chromosomes

Front 2

centromere

Back 2

the constricted area of each chromatid

Front 3

chromatid

Back 3

a half of the chromosome

Front 4

diploid

Back 4

a cell that has two sets of chromosomes

Front 5

haploid

Back 5

a cell that contains only one set of chromosomes

Front 6

histone

Back 6

protein in which DNA is tightly wrapped around

Front 7

homologous chromosomes

Back 7

two copies of identical autosomes

Front 8

karyotype

Back 8

a photomicrograph of the chromosomes in a dividing cell in a normal human

Front 9

nonhistone

Back 9

generally involved in controlling the activity of specific regions of the DNA

Front 10

sex chromosome

Back 10

chromosome that determines the sex of an organism

Front 11

anaphase

Back 11

the third stage in the cell cycle

Front 12

binary fission

Back 12

the division of a prokaryotic cell into two genetically identical offspring cells

Front 13

cell cycle

Back 13

the repeating set of events that make up the life of a cell

Front 14

cell plate

Back 14

cleavage furrow but for plant cells

Front 15

centriole

Back 15

small cylindrical body in the centrosomes

Front 16

centrosome

Back 16

a dark spot, that is part of a pair, that appears next to the disappearing nucleus

Front 17

cleavage furrow

Back 17

the area of the cell membrane that pinches in and eventually separates the dividing cell into two cells

Front 18

cytokenesis

Back 18

the division of the cytoplasm of the cell

Front 19

G0 phase

Back 19

a phase in which cells do not copy their DNA and do not prepare for cell division

Front 20

G1 phase

Back 20

first phase of interphase, cell grows to maturity

Front 21

G2 phase

Back 21

the phase between DNA synthesis and cell division

Front 22

interphase

Back 22

the time between cell divisions

Front 23

kinetochore

Back 23

a disk - shaped protein that is formed in the centromere region of each chromosome

Front 24

kinetochore fibers

Back 24

spindle fibers that attach to a kinetochore

Front 25

meiosis

Back 25

reduces the chromosome number by half in new cells

Front 26

metaphase

Back 26

the second phase of mitosis

Front 27

mitosis

Back 27

results in new cells that are identical to that of the original cell

Front 28

mitotic spindle

Back 28

an array of spindle fibers meant to equally divide the chromatids between the two offspring cells

Front 29

M phase

Back 29

the phase in which the nucleus of a cell divides

Front 30

polar fibers

Back 30

extend across the dividing cell from centrosome to centrosome

Front 31

prophase

Back 31

the first step of mitosis

Front 32

S phase

Back 32

the cell's DNA is copied

Front 33

spindle fiber

Back 33

made of microtubules, radiate from the centrosomes in preparation for mitosis

Front 34

telophase

Back 34

the fourth phase of mitosis

Front 35

crossing-over

Back 35

when portions of chromatids break off and attach to adjacent chromatids on the homologous chromosome

Front 36

gamete

Back 36

a haploid reproductive cell

Front 37

genetic recombination

Back 37

producing a new mixture of genetic material

Front 38

independent assortment

Back 38

the random separation of the homologous chromosomes

Front 39

oogenesis

Back 39

the production of mature egg cells

Front 40

polar body

Back 40

other products of meiosis

Front 41

spermatid

Back 41

formed by the meiotic splitting of a diploid cell

Front 42

spermatogenesis

Back 42

the production of sperm cells

Front 43

synapsis

Back 43

the pairing of homologous chromosomes

Front 44

tetrad

Back 44

each pair of homologous chromosomes