biology t3 exam 2023

Question 1

DNA

Answer 1

Deoxyribonucleic acid. Carries genetic information and can not leave the nucleus of a cell. The structure formed is called a double helix.

Question 2

nucleotide

Answer 2

The building block of all nucleic acids, which include DNA and RNA.

Question 3

nitrogenous base

Answer 3

a component of nucleotides.

Question 4

complimentary base

Answer 4

strands that connect to eachother. for example, A&T, C&G.

Question 5

Protein

Answer 5

a molecule made up of amino acids

Question 6

Allele

Answer 6

variant of a gene

Question 7

Homozygous

Answer 7

having two identical alleles of a particular gene or genes.

Question 8

Heterozygous

Answer 8

having two different alleles of a particular gene or genes.

Question 9

Phenotype

Answer 9

physical characteristic (what you look like)

Question 10

Genotype

Answer 10

genetic makeup (what your genes are)

Question 11

Dominant

Answer 11

Alleles are expressed in capital letters, eg TT or Tt, this is the gene which will be expressed no matter what it is paired with.

Question 12

Reccessive

Answer 12

Alleles are expressed with lowercase letters, they represent the gene that will be less likely to occur. This gene will only occur if there are two lower case letters, eg tt

Question 13

Eukaryotes

Answer 13

single celled organisms with a nucleus

Question 14

Prokaryotes

Answer 14

single celled organsisms without a nucleus or other membrane bound organelles

Question 15

Mitosis

Answer 15

Part of the cell cycle which replicated chromosomes are separated into 2 new nuclei

Question 16

Gamete

Answer 16

reproductive cell sperm/egg

Question 17

zygote

Answer 17

fertilised egg

Question 18

haploid

Answer 18

a cell with only one set of two chromosomes

Question 19

diploid

Answer 19

a cell with two sets of chromosomes (human cell)

Question 20

centromere

Answer 20

central part of a chromosome

Question 21

P arm

Answer 21

shortest arm of a chromosome

Question 22

Q arm

Answer 22

longest arm of a chromosome

Question 23

codon

Answer 23

a sequence of 3 nucleotides in a DNA/RNA molecule which code for an amino acid (eg, CAG, ACG)

Question 24

mRNA

Answer 24

messenger RNA, a type of RNA polymerase using DNA as a template

Question 25

tRNA

Answer 25

transfer RNA

Question 26

transcription

Answer 26

the process of copying a segment of RNA into DNA. comes BEFORE translation (remember, you have to transcribe something before you can translate it)

Question 27

translation

Answer 27

the process by which a cell makes proteines using genetic info in mRNA