chapter 2: Mendel and the Pea

Question 1

Mitosis:

Answer 1

cell division to produce more cells

Question 2

differentiation:

Answer 2

development

Question 3

23 egg (mother)
23 sperm (father)

Answer 3

=46 fertilised eggs

Question 4

mitosis phases:

Answer 4

parent cell with four chromosomes (interphase)

Question 5

chromosomes are duplicated (prophase)

Answer 5

chromosomes align in middle of the cell (metaphase)

Question 6

chromatids now split to opposite cell poles (anaphase)

Answer 6

2 daughter cells form, identical to the original (telophase)

Question 7

chromosomes:

Answer 7

large bodies which are composed of one long strand of DNA wrapped around proteins called histones and are supercoiled

Question 8

chromatin:

Answer 8

partially coiled DNA. This is normal state of the DNA when cell is not dividing.

Question 9

DNA:

Answer 9

a very special molecule which carries information of the species, and individual traits.

Question 10

Genes:

Answer 10

parts of DNA that carry a code for the structure of proteins. These genes give us our characteristics.

Question 11

allele

Answer 11

an alternative for of the gene

Question 12

diploid:

Answer 12

a cell or nucleus containing two complete sets of chromosomes, one from each parent

Question 13

haploid:

Answer 13

having a single set of unpaired chromosomes

Question 14

zygote:

Answer 14

a diploid cell resulting from the fusion of two haploid gametes

Question 15

homologous chromosomes:

Answer 15

similar in position, structure and evolutionary origin but not necessarily in function

Question 16

chromatid:

Answer 16

each of the two tread like strands into which a chromosome divides longitudinally during cell division, each contains a double helix of DNA

Question 17

spindle:

Answer 17

a slender mass of micro tubes formed when a cell divides. At metaphase the chromosomes become attached to it by their centromeres before being pulled towards its ends

Question 18

fertilization

Answer 18

the action or process of fertilizing an egg, involving the fusion of the male and female gametes to form a zygote

Question 19

gametes

Answer 19

a mature haploid male or female germ cell that is able to unite with another of the opposite sex in sexual reproduction to form a zygote

Question 20

P1

Answer 20

the parents

Question 21

F1

Answer 21

the hybrid offspring of these strains

Question 22

F2

Answer 22

the offspring produced by matings between F1 individuals, the grandchildren of P1

Question 23

genotype:

Answer 23

combination of alleles

Question 24

phenotype:

Answer 24

trait

Question 25

dominant allele:Y

Answer 25

recessive allele: y

Question 26

heterozygous (hybrid) Yy

Answer 26

Homozygous dominant (pure) YY

Question 27

Homozygous recessive (pure) yy

Answer 27

dominant: most important

Question 28

recessive:

Answer 28

denoting heritable characteristics controlled by genes that are expressed in offspring only when inherited from both parents

Question 29

homozygous:

Answer 29

when an individual has two of the same allele, either dominant or recessive

Question 30

heterozygous:

Answer 30

having one of each of two different alleles

Question 31

mono hybrid cross:

Answer 31

the mating of two different individuals with different variations at one genetic chromosome of interest

Question 32

test crosses:

Answer 32

a genetic cross between a homozygous recessive and a corresponding suspected heterozygote to determine the genotype of the latter

Question 33

purebred:

Answer 33

bred from parents of the same breed of variety

Question 34

hybrid:

Answer 34

the offspring of two plants or animals of different species or varieties