Unit 3 List 2 DNA & Heredity GLW

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

threadlike structures made of protein and a single molecule of DNA that serve to carry the genomic information from cell to cell

Question 5

codon

Answer 5

A codon is a trinucleotide sequence of DNA or RNA that corresponds to a specific amino acid.

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

diploid

Answer 9

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

Question 10

DNA

Answer 10

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

Question 11

fertilization

Answer 11

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

Question 12

frameshift

Answer 12

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

Question 13

gamete

Answer 13

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

Question 14

gene

Answer 14

(in informal use) a unit of heredity which is transferred from a parent to offspring and is held to determine some characteristic of the offspring.

Question 15

gene mutation

Answer 15

a change in one or more genes

Question 16

genetic code

Answer 16

Genetic code refers to the instructions contained in a gene that tell a cell how to make a specific protein.

Question 17

genetic variation

Answer 17

Without genetic variation, some key mechanisms of evolutionary change like natural selection and genetic drift cannot operate.

Question 18

haploid

Answer 18

Haploid refers to the presence of a single set of chromosomes in an organism’s cells

Question 19

homologous chromosome

Answer 19

made up of chromosome pairs of approximately the same length, centromere position, and staining pattern, for genes with the same corresponding loci

Question 20

independent assortment

Answer 20

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

Question 21

insertion

Answer 21

the action of inserting something.

Question 22

meiosis

Answer 22

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

Question 23

meiosis I

Answer 23

the number of cells is doubled but the number of chromosomes is not

Question 24

meiosis II

Answer 24

the second division in meiosis in which chromatids of each chromosome are segregated equally into daughter cells

Question 25

monosomy

Answer 25

the condition in which only one chromosome from a pair is present in cells rather than the two copies usually found in diploid cells

Question 26

mutagen

Answer 26

Anything that causes a mutation (a change in the DNA of a cell)

Question 27

mutation

Answer 27

Any change in the DNA sequence of a cell.

Question 28

nondisjunction

Answer 28

a pair of homologous chromosomes has failed to separate or segregate at anaphase so that both chromosomes of the pair pass to the same daughter cell

Question 29

offspring

Answer 29

the young creation of living organisms, produced either by sexual or asexual reproduction

Question 30

parent cell

Answer 30

A cell that is the source of other cells

Question 31

point mutation

Answer 31

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

Question 32

replication

Answer 32

the action of copying or reproducing something.

Question 33

sexual reproduction

Answer 33

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

Question 34

somatic cell

Answer 34

cells in the body other than sperm and egg cells

Question 35

substitution

Answer 35

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

Question 36

trisomy

Answer 36

a chromosomal condition characterised by an additional chromosome

Question 37

trait

Answer 37

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