Chapter 7a

Question 1

deoxyribonucleic acid (DNA) 

Answer 1

a double-stranded nucleic acid
chain made up of nucleotides.
DNA carries the instructions for
proteins which are required for
cell and organism survival

Question 2

nucleic acid

Answer 2

the class of
macromolecules that includes
DNA and RNA. All nucleic
acids are polymers made out of
nucleotide monomers

Question 3

nucleotide 

Answer 3

the monomer unit
of nucleic acids. Made up of
a nitrogen-containing base, a
sugar molecule (ribose in RNA
and deoxyribose in DNA), and a
phosphate group

Question 4

Nitrogen containing bases

Answer 4

− adenine (A)
− thymine (T)
− guanine (G)
− cytosine (C

Question 5

gene 

Answer 5

a section of DNA that
carries the code to make a protein

Question 6

Genome

Answer 6

the complete set of
DNA contained within an
organism’s chromosomes

Question 7

allele

Answer 7

alternate forms of a gene

Question 8

locus (pl. loci) 

Answer 8

the fixed position
on a chromosome where a
particular gene is located

Question 9

Inheritance

Answer 9

the genetic
transmission of traits from parent
to offspring

Question 10

Phenotype

Answer 10

 the observable trait of
an individual

Question 11

genotype

Answer 11

is a set of genes in DNA responsible for unique traits or characteristics

Question 11

haploid 

Answer 11

describes a single set
of chromosomes (n)

Question 12

histone protein

Answer 12

highly basic
proteins that associate with DNA
inside the nucleus and help it
condense into a chromosome
allowing it to fit inside the nucleus

Question 13

chromosome 

Answer 13

the structure made
of protein and nucleic acids that
carries genetic information

Question 14

somatic cell 

Answer 14

any cell that is not a reproductive cell (such as sperm
and egg cells). Somatic cells are diploid (2n), meaning they contain
two sets of chromosomes – one inherited from each parent

Question 15

chromatid 

Answer 15

one half of a replicated
chromosome. Prior to cell division,
chromosomes are duplicated and
two copies join together at their
centromeres (joined chromatids
are known as sister chromatids)

Question 16

homologous chromosomes

Answer 16

A pair of chromosomes of similar
length, gene position, and
centromere location. One of the
pair is inherited from the mother
(maternal chromosome) and
the other from the father
(paternal chromosome)

Question 17

homologue 

Answer 17

a homologous
chromosome

Question 18

karyotype 

Answer 18

a visual representation
of an individual’s entire genome
organised into homologous pairs

Question 19

autosome 

Answer 19

any chromosome
(1–22) in humans that is not
a sex chromosome

Question 20

sex chromosome

Answer 20

a chromosome
responsible for determining the
biological sex of an organism.
In humans, sex chromosomes can
be either an X or Y chromosome

Question 21

aneuploidy

Answer 21

when a cell or
organism varies in the usual
number of chromosomes in its
genome by the addition or loss
of a chromosome

Question 22

polyploidy

Answer 22

when an organism
contains additional sets of
chromosomes in its genome

Question 23

monosomy

Answer 23

a genetic abnormality
where an organism has one
missing chromosome

Question 24

trisomy

Answer 24

a genetic abnormality
where an organism has one
extra chromosome

Question 25

tetrasomy 

Answer 25

a genetic abnormality
where an organism has two
extra chromosome