Bio 101 Chapter 13 Campbell

Front 1

What is a SOMATIC CELL?

Back 1

any cell other than a sex cell; has 46 chromosomes; Mt

Front 2

What are GAMETES?

Back 2

sex cells; sperm and egg made in testes and ovaries

Front 3

What are SEX CHROMOSOMES?

Back 3

females have a homologous pair of X chromosomes and makes have an X and Y chromosome; they determine a cell's sex

Front 4

Autosomes

Back 4

all chromosomes that are not sex chromosomes

Front 5

Homologous chromosomes (Homologs)

Back 5

A pair of chromosomes that have the same length and centromere position

Front 6

Diploid Cell

Back 6

A Cell with 2 chromosome sets - Somatic Cell; the diploid number for humans is 46

Front 7

Haploid Cell

Back 7

Gamete are only haploid Cells; haploid number for humans is 23 (22 autosomes and 1 sex chromosome); meiosis occurs during production of gametes

Front 8

Non-Sister Chromatids

Back 8

Any Two chromatids in a pair of homologous chromosomes that are not sister chromatids

Front 9

Sister Chromatids

Back 9

Two copies of one chromosome, closely associated along their lengths

Front 10

Homologous Pair

Back 10

Two Chromosomes in a dipold cell with the same shape and content, one from the male parent, the other from the female parent.

Front 11

Fertilization

Back 11

The union of gametes

Front 12

Zygote

Back 12

Fertilized egg; diploid; divides by mitosis to make an organism; because it contains two haploid sets of chromosomes bearing genes from both parents

Front 13

Germ Cells

Back 13

Specialized cells in the gonads that produce gametes

Front 14

Reductional Phase of Meiosis

Back 14

Meiosis I - # of chromosomes gets reduced in Half (from diploid to haploid)

Front 15

Equational Phase of Meiosis

Back 15

Meiosis II - sister chromatids separate during MII, producing haploid daughter cells; MII and Mt are identical

Front 16

Meiosis of female gametes results in #? viable cell called a(n) ____ and #? non-viable cells called _______

Back 16

Meiosis of female gametes results in 1 viable cell called a(n) _ovum (egg)_ and 3 non-viable cells called _polar bodies_

Front 17

Sister Chromatid Cohesion

Back 17

The binding of sister chromatids to form one chromosome

Front 18

One replicated Chromosome is composed of two. . .

Back 18

. . . sister chromatids

Front 19

Two stages of Meiosis result in #? daughter cells

Back 19

Two stages of Meiosis result in 4 daughter cells each with only half as many chromosomes as the parent cell

Front 20

Alleles

Back 20

Different versions of genes in homologous chromosomes

Front 21

What separates during Meiosis I?

Back 21

Homologous Chromosomes

Front 22

What separates during Meiosis II?

Back 22

Sister Chromatids

Front 23

Prophase I

Back 23

Synapsis and crossing over occur; duplicate homologous chromosomes combine for form 46 sister chromatids and exchange of DNA; chromosomes condense and the nuclear membrane begins to fragment

Front 24

Metaphase I

Back 24

2x2 chromatids align along the metaphase plate

Front 25

Anaphase I

Back 25

homologous chromosomes separate and move toward opposite poles, (moving in pairs)

Front 26

Telophase I & Cytokinesis

Back 26

nuclear membrane reform and the chromosomes decondense. The two cells are separated by a cleavage furrow. Two daughter cells = haploids with 23 copies of chromosomes

Front 27

Prophase II

Back 27

sister chromatids condense and the spindles starts to form. Nuclear membrane begins to fragment

Front 28

Metaphase II

Back 28

Chromosomes position themselves along the Metaphase plate - Due to crossing over in Meiosis I, Sister Chromatids are *NOT* genetically identical.

Front 29

Anaphase II

Back 29

Sister Chromatids separate due to breakdown of proteins at the centromere and move towards poles, poles elongates pole

Front 30

Telophase II and Cytokinesis

Back 30

chromosomes decondense and nuclear membrane reform. Cleavage furrow separates the 2 cells into 4 cells. 4 Haploid, single-stranded, Daughter Cells form

Front 31

Synapsis

Back 31

The binding of two homologous chromosomes; two chromatids become physically connected

Front 32

Crossing Over

Back 32

Genetic rearrangement of between two nonsister chromatids; occurs during prophase I

Front 33

Chiasma

Back 33

Point of a crossing over in a chromosome

Front 34

Cohesins

Back 34

Protein complexes that join sister chromatids along the lengths

Front 35

Female Chromosome

Back 35

X

Front 36

Male Chromosome

Back 36

Y

Front 37

Recombinant Chromosomes

Back 37

Individual Chromosomes that carry genes derived from different parents. A result of crossing over.

Front 38

What is HEREDITY?

Back 38

the transmission of trains from one generation to the next

Front 39

What is VARIATION?

Back 39

Offspring differ somewhat in appearance from parents and siblings

Front 40

What is GENETICS?

Back 40

the study of heredity and variation

Front 41

Three events unique to Meiosis

Back 41

synapsis and crossing over; tetrads on the metaphase plate; separation of homologues

Front 42

tetrads on the metaphase plate

Back 42

at metaphase MI, paired homologous chromosomes are positioned on the metaphase plate, rather than individual replicated chromosomes in Mt

Front 43

separation of homologues

Back 43

at anaphase MI, the duplicated chromosomes of each homologous pair move toward opposite poles, but the sister chromatids of each duplicated chromosome remain attached. in Mt, sister chromatids separate

Front 44

tetrad or bivelent

Back 44

4 chromatids; 2 and 2 lined up

Front 45

what occurs between MI and MII?

Back 45

nothing; interphase does not occur because no need to replicate