Unit 3 List 2 DNA & Heredity

Question 1

allele

Answer 1

one of two or more alternative forms of a gene that arise by mutation and are found at the same place on a chromosome.

Question 2

centromere

Answer 2

the region of a chromosome to which the microtubules of the spindle attach, via the kinetochore, during cell division.

Question 3

chromatid

Answer 3

one of the two identical halves of a chromosome that has been replicated in preparation for cell division.

Question 4

chromosome

Answer 4

a threadlike structure of nucleic acids and protein found in the nucleus of most living cells, carrying genetic information in the form of genes.

Question 5

codon (chart)

Answer 5

, shows all of the possible three letter combinations of mRNA nucleotides, and for which amino acid each combination codes for.

Question 6

crossing over

Answer 6

a cellular process that happens during meiosis when chromosomes of the same type are lined up.

Question 7

daughter cell

Answer 7

the cells that are formed after cell division.

Question 8

deletion

Answer 8

the removal or obliteration of written or printed matter, especially by drawing a line through it.

Question 9

DNA

Answer 9

the molecule that carries genetic information for the development and functioning of an organism.

Question 9

diploid

Answer 9

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

Question 10

fertilization

Answer 10

a complex multi-step process that is complete in 24 hours.

Question 11

frameshift

Answer 11

a genetic mutation caused by a deletion or insertion in a DNA sequence that shifts the way the sequence is read.

Question 12

gene mutation

Answer 12

a change in one or more genes.

Question 12

gamete

Answer 12

a reproductive cell of an animal or plant.

Question 12

gene

Answer 12

The basic unit of heredity passed from parent to child.

Question 12

genetic variation

Answer 12

the variation in the DNA sequence in each of our genomes.

Question 13

genetic code

Answer 13

the nucleotide triplets of DNA and RNA molecules that carry genetic information in living cells.

Question 14

haploid

Answer 14

a cell that contains a single set of chromosomes.

Question 15

homologous chromosome

Answer 15

pairs of chromosomes in a diploid organism that have similar genes, although not necessarily identical.

Question 16

independent assortment

Answer 16

describes how different genes independently separate from one another when reproductive cells develop.

Question 17

insertion

Answer 17

he action of inserting something.

Question 18

meiosis

Answer 18

a type of cell division in sexually reproducing organisms that reduces the number of chromosomes in gametes

Question 18

meiosis I

Answer 18

a type of cell division unique to germ cells,

Question 19

meiosis II

Answer 19

a mitotic division of each of the haploid cells produced in meiosis

Question 20

mutagen

Answer 20

In genetics, a mutagen is a physical or chemical agent that permanently changes genetic material, usually DNA, in an organism and thus increases the frequency of mutations above the natural background level.

Question 21

mutation

Answer 21

Any change in the DNA sequence of a cell.

Question 22

nondisjunction

Answer 22

the failure of the chromosomes to separate, which produces daughter cells with abnormal numbers of chromosomes.

Question 23

offspring

Answer 23

a person’s child or children.

Question 24

parent cell

Answer 24

A cell that is the source of other cells,

Question 25

replication

Answer 25

the action of copying or reproducing something.

Question 25

point mutation

Answer 25

occurs in a genome when a single base pair is added, deleted or changed.

Question 26

sexual reproduction

Answer 26

the production of new organisms by the combination of genetic information of two individuals of different sexes.

Question 27

somatic cell

Answer 27

any cell of a living organism other than the reproductive cells.

Question 27

substitution

Answer 27

the action of replacing someone or something with another person or thing.

Question 28

trisomy

Answer 28

a chromosomal condition characterised by an additional chromosome.

Question 29

trait

Answer 29

a distinguishing quality or characteristic, typically one belonging to a person.