Science

Question 1

gamete

Answer 1

a sex cell containing half the number of chromosomes of other body cells

Question 2

sperm

Answer 2

the male gamete of animals

Question 3

ovum

Answer 3

the female gamete of animals and some plants

Question 4

haploid

Answer 4

a nucleus that contains one complete set of chromosomes; usually found in a gamete

Question 5

diploid

Answer 5

a nucleus that contains two complete sets of chromosomes

Question 6

meiosis

Answer 6

the process that results in the formation of gametes with half the genetic material of the parent cell

Question 7

deoxyribonucleic acid (DNA)

Answer 7

a molecule that contains all the instructions for every job performed by the cell; this information can be passed from one generation to the next

Question 8

nucleotide

Answer 8

the building block of DNA consisting of a deoxyribose sugar, phosphate and nitrogen base

Question 9

adenine

Answer 9

a nucleotide of DNA or RNA; complementary to thymine in DNA and uracil in RNA

Question 10

guanine

Answer 10

a nucleotide of DNA or RNA; complementary to cytosine

Question 11

cytosine

Answer 11

a nucleotide of DNA or RNA; complementary to guanine

Question 12

thymine

Answer 12

a nucleotide of DNA; complementary to adenine

Question 13

complementary base

Answer 13

a nucleotide base that pairs with its partner nucleotide on the alternative DNA strand. Adenine pairs with thymine, and cytosine pairs with guanine

Question 14

ribonucleic acid

Answer 14

(RNA) a complementary copy of DNA that is able to carry the genetic message from the nucleus to the cytoplasm

Question 15

bivalent chromosome

Answer 15

a chromosome that has duplicated, consisting of two sister chromatids joined at a centromere

Question 16

chromatid

Answer 16

one half of a duplicated chromosome

Question 17

karyotype

Answer 17

the arrangement of a complete set of chromosomes in pairs of decreasing size

Question 18

gene

Answer 18

a specific sequence of DNA that codes for a particular trait, usually a protein

Question 19

transcription

Answer 19

the formation of complementary RNA from DNA

Question 20

codon

Answer 20

sequence of 3 nitrogen bases in RNA

Question 21

translation

Answer 21

the formation of a protein from RNA; occurs on a ribosome

Question 22

principle of segregation

Answer 22

pairs of gene variants are separated into reproductive cells

Question 23

principle of independent assortment

Answer 23

the inheritance of one set of factors from one parent is separate from the inheritance of other factors

Question 24

mutagen

Answer 24

a chemical or physical agent that causes a change in DNA

Question 25

genetic mutation

Answer 25

a permanent change in the sequence of nucleotides in DNA

Question 26

allele

Answer 26

a version of a gene. Each person inherits one allele from each parent

Question 27

homozygous

Answer 27

having two identical alleles for a particular trait

Question 28

heterozygous

Answer 28

having two different alleles for a particular trait; a carrier for the recessive trait

Question 29

dominant trait

Answer 29

a characteristic that needs only one copy of an allele to appear in the physical appearance of an organism

Question 30

recessive trait

Answer 30

a characteristic that results from the inheritance of two identical alleles

Question 31

carrier

Answer 31

a person who is heterozygous and therefore has one recessive allele that is not expressed in their phenotype

Question 32

genotype

Answer 32

the combination of alleles for a particular trait

Question 33

phenotype

Answer 33

the physical characteristics that result from an interaction between the genotype and the environment

Question 34

Punnett square

Answer 34

a diagram that is used to predict the outcome of breeding organisms

Question 35

autosome

Answer 35

a chromosome that does not determine the sex of an organism

Question 36

sex chromosome

Answer 36

a chromosome that determines the sex of an organism

Question 37

pedigree

Answer 37

a diagram showing the inheritance pattern of a particular trait

Question 38

vector

Answer 38

an agent (often a bacteria or virus) used to deliver a trans-gene

Question 39

genetic screening

Answer 39

the testing of a cross section of individuals to determine whether they have a particular trait or disease

Question 40

gene probe

Answer 40

short sections of nucleotides known to be complementary to the genetic sequence of interest

Question 41

genetic testing

Answer 41

the testing of an individual to determine whether they have a particular trait or disease

Question 42

stem cell

Answer 42

a cell that can produce a number of different types of cells. Adult stem cells can produce a limited number of cell types (e.g. skin stem cells), whereas embryonic stem cells can produce multiple types of cells