Chapter 5 Meiosis

Front 1

prophase 1

Back 1

condensation of chromosomes into threads, homologous pairs, crossing over, homologs seperate at centromeres chiasmata, nuclear membrane breakdown.

Front 2

Metaphase

Back 2

homologous pairs line up, metaphase plate

Front 3

Anaphase 1

Back 3

homologous pairs seperate, no centromeric division

Front 4

Telophase 1

Back 4

cytokinesis/ 2 cells

Front 5

chromosomal reduction

Back 5

tetrads seperate, between telophase and Meiosis 1

Front 6

Interkinesis

Back 6

no further synthesis of DNA, resting stage

Front 7

Prophase II

Back 7

No synapsis , chromosomes condense, nuclear membrane breakdown

Front 8

Metaphase II

Back 8

Chromosomes line up on metaphase plate

Front 9

Anaphase II

Back 9

Chromosomes seperate to poles, centromere divides

Front 10

Telophase II

Back 10

cytokinesis, four cells (half chromosome number), nuclear membrane reforms

Front 11

Equational cytoplasmic division

Back 11

chromatids seperate,

Front 12

Which of the following is NOT correct about meiosis?
A) Meiosis produces haploid gametes from diploid cells
B) Meiosis has one reductional division and two cytoplasmic divisions
C) Unlike mitosis, chromosomes are duplicated twice in interphase
D) In meiosis, homologous chromosomes meet in synapsis to form tetrads
E) All of the above are correct

Back 12

e) all of the above

Front 13

In a monohybrid cross of an individual with an AA genotype with another of aa genotype, the phenotypic ratio of the offspring would be:
A) 100 percent dominant
B) 50 percent dominant; 50 percent recessive
C) 100 percent recessive
D) 75 percent dominant; 25 percent recessive

Back 13

A) 100 percent dominant

Front 14

One way of determining if an individual is homozygous or heterozygous dominant for a particular trait is to conduct a testcross with that individual.
True or false

Back 14

True

Front 15

Which of the following is true in a case of intermediate inheritance?
A) Neither allele is completely dominant over the other
B) The heterozygote phenotype appears either intermediate between or distinct from those of the parent.
C) One allele is always dominant over the other
D) Both A and B are correct

Back 15

D) Both A and B are correct

Front 16

Nucleic acids are composed of repeated units called nucleotides, each of which is composed of a five-carbon sugar, a nitrogenous base, and a protein.

True or False

Back 16

False

Front 17

Every time a cell divides, the structure of DNA must be precisely copied in the daughter cells in a process called:
A) Replication
B) Templation
C) Complementation

Back 17

A) Replication

Front 18

A codon is composed of three nucleotides and there are 64 possible codons in RNA.
True or False

Back 18

True

Front 19

Transfer RNA has a sequence of three bases called the anticodon that forms base pairs with complementary bases on the messenger RNA.
True or False

Back 19

True

Front 20

Allele

Back 20

Alternate forms of genes coding for the same trait; situated at the same locus

Front 21

Diploid:

Back 21

A cell that contains both chromosomes of a homologous pair.

Front 22

Haploid:

Back 22

A cell that has only one chromosome of each homologous pair. The fusion of 2 haploid cells creates a diploid cell (fertilized egg)

Front 23

Gamete:

Back 23

Sex cell.

Front 24

Humans have 46 chromosomes consisting of 23 homologous pairs.

Back 24

Each parent donates one chromosome to each of the 23 homologous pairs. I.e., half of an individual’s chromosomes come from the female parent while half come from the male parent.

Front 25

Reproductive cells – haploid (n) sex cells

Back 25

These cells are called gametes and contain only half the number of chromosomes. If one somatic cell is fertilized by another, the resulting zygote would contain twice the number of chromosomes. I.e., the chromosome number would double each generation. For this reason, the chromosome number must be reduced during the production of gametes. This way, one haploid gamete is fertilized by another and the resulting zygote is diploid.

Front 26

diploid number:** Eggs and sperm contain only 1/2 the diploid number of chromosomes.

Back 26

the number of chromosomes found in the double set of chromosomes found in all body cells (2n)