3.1 Genetics and Inheritance

Question 1

Genetics

Answer 1

Study of heredity

Question 2

Heredity

Answer 2

Characteristics passed from parents to their offspring

Question 3

Number of chromosomes for fruit flies

Answer 3

8 pairs

Question 4

Number of chromosomes for humans

Answer 4

23 pairs

Question 5

Genes

Answer 5

Stretches of DNA that are specific to a particular characteristic

Question 6

Alleles

Answer 6

Versions of genes that code for a specific characteristic’s trait

Question 7

Gregor Mendel

Answer 7

Austrian monk known for demonstrating concepts of genetics and inheritance

Question 8

Breeding

Answer 8

Mating and production of offspring of living organisms such as plants and animals.

Question 9

True-breeding

Answer 9

Plants in which the offspring have exhibited the same traits over many generations

Question 10

Crossbreeding

Answer 10

Breeding in which different species or varieties are mated with each other to produce a hybrid, which contains features of both parents

Question 11

Pollination

Answer 11

Act of transferring pollen from the male part of the plant to the female part of the plant

Question 12

P generation

Answer 12

True-bred, homozygous parents

Question 13

F1 generation

Answer 13

First generation of hybrid offspring

Often identifies the dominant gene

Question 14

F2 generation

Answer 14

Effects of hybridization start to show

Mixture of traits is represented

Question 15

Phenotypes

Answer 15

Set of observable characteristics of an organism

Question 16

Genotype

Answer 16

Genetic composition that determines a phenotype

Question 17

Homozygous

Answer 17

Having two copies of the same allele, true-bred

Question 18

Heterozygous

Answer 18

Containing both the dominant and recessive gene

Question 19

Law of segregation

Answer 19

Every organism acquires two alleles for each trait, one from each parent, in a random fashion

Question 20

Law of independent assortment

Answer 20

Separation of alleles for a given gene occurs independently of any other gene (given that they are not on the same chromosome)

Question 21

Linked genes

Answer 21

Genes located on the same chromosome that tend to be inherited together

Question 22

Dominant gene

Answer 22

Always completely expressed if it is present in the organism’s genetic code even if only one allele present

Question 23

Recessive allele

Answer 23

Only completely expressed if both parents contributed recessive alleles.

Question 24

Law of dominance

Answer 24

When present, dominant alleles will always be expressed, while recessive alleles are only express when the recessive allele is homozygous

Question 25

Punnet square

Answer 25

Chart that shows the different ways alleles from two parents can combine and be passed on to offspring

Question 26

Dihybrid crossing

Answer 26

Two-factor crossbreeding

Question 27

Mono hybrid crossbreeding

Answer 27

Involving only one gene

Question 28

Incomplete dominance

Answer 28

An intermediate phenotype that is a mix of both parents will occur

Question 29

Codominance

Answer 29

Both phenotypes are expressed (not blended)

Question 30

Environmental influences

Answer 30

How the external world affects an organism

Question 31

Exceptions to the rules of Mendelian genetics

Answer 31

Incomplete dominance Codominance Environmental effects