Genetic Crosses & Heredity (chpt. 16)

Question 1

Heredity

Answer 1

The passing on of features from parents to offspring by means of genes

Question 2

Chromosomes

Answer 2

Thread-like structures made of DNA found in the nucleus

Question 3

DNA

Answer 3

Deoxyribonucleic acid

Question 4

Autosomes

Answer 4

Chromosomes that do not determine sexuality

Question 5

Sex chromosomes

Answer 5

X and Y chromsomes

Question 6

Sex chromosomes for a human female

Answer 6

XX

Question 7

Sex chromosomes for a human male

Answer 7

XY

Question 8

Mitosis

Answer 8

A type of cell division where the parent cell divides to produce two identical daughter cells

Question 9

Meiosis

Answer 9

A type of cell division where the parent cell divides to produce daughter cells with half the number of chromosomes as the parent

Question 10

Haploid cell

Answer 10

Contains one set of chromosomes

Question 11

Diploid cell

Answer 11

Contains two sets of chromosomes

Question 12

Gametes

Answer 12

Sex cells - egg & sperm

Question 13

Gene

Answer 13

DNA that codes to make a protein

Question 14

Locus

Answer 14

The position of a gene on a chromosome

Question 15

Allele

Answer 15

An alternative form of a gene

Question 16

Homozygous

Answer 16

Both alleles are identical

Question 17

Heterozygous

Answer 17

Both alleles are different

Question 18

Dominant gene

Answer 18

The gene expressed in the heterozygous condition. It prevents a recessive gene from working

Question 19

Recessive gene

Answer 19

A gene that can be prevented from working by a dominant gene

Question 20

Somatic cells

Answer 20

All body cells except sex cells

Question 21

Genotype

Answer 21

The genetic make up of an organism i.e. the genes present

Question 22

Phenotype

Answer 22

The physical appearance of an organism

Question 23

Punnet square

Answer 23

A grid used to show the possible genotypes of offspring in a genetic cross

Question 24

Progeny

Answer 24

The offspring produced

Question 25

Mono hybrid cross

Answer 25

Contains one trait
PRACTICE

Question 26

Dihybrid cross

Answer 26

Contains two traits
PRACTICE

Question 27

Mendel's law of segregation (first law)

Answer 27

States that inherited characteristics are controlled by pairs of alleles. These alleles separate at gamete formation, with only one member of the pair being found in each gamete

Question 28

Mendel's law of segregation (first law)

Answer 28

States that inherited characteristics are controlled by pairs of alleles. These alleles separate at gamete formation, with only one member of the pair being found in each gamete

Question 29

Mendel's law of independent assortment (second law)

Answer 29

States that when gametes are formed either of a pair of alleles is equally likely to combine with either of another pair of alleles

Question 30

Mendel's law of independent assortment (second law)

Answer 30

States that when gametes are formed either of a pair of alleles is equally likely to combine with either of another pair of alleles

Question 31

Father of genetics

Answer 31

Gregor mendel

Question 32

Who is Gregor Mendel

Answer 32

The father of genetics

Question 33

Linked genes

Answer 33

Do not assort independently as they are passed on to a gamete on the same chromosome
Causes less variation among offspring

Question 34

Incomplete dominance / co-dominance

Answer 34

Neither allele is dominant, both alleles are equally expressed in the heterozygous condition
E.g. in snapdragons and shorthorn cattle

Question 35

Sex-linkage

Answer 35

A characteristic controlled by a sex chromosome
E.g. haemophilia, albinism, colour blindness

Question 36

Progeny

Answer 36

Refers to the offspring produced

Question 37

Pedigree

Answer 37

A diagram showing the genetic history of a group of related individuals