DNA and Proteins

Question 1

what is a DNA nucleotide made up of

Answer 1

• nitrogen base (ATCG)
• phosphate
• DEOXYribose suger

Question 2

what holds the two strands of DNA together in the shape of a double helix

Answer 2

weak hydrogen bonds

Question 3

what is the shape of DNA in prokaryotic cells

Answer 3

circular, 1 piece of DNA

Question 4

where is dna located in prokaryotic cells

Answer 4

the nucleoid region (no nucleus)

Question 5

do prokaryotic cells have membrane bound organelles?

Answer 5

No, they do have ribosomes though

Question 6

Describe the shape of DNA in eukaryotic cells

Answer 6

Linear (like chromosomes)

Question 7

describe the shape of DNA

Answer 7

double stranded, double helix

Question 8

what are the complementary base pairings in DNA

Answer 8

A + T (adenine + thymine)
G + C (guanin + cytosine)

Question 9

what are the two types of nucleic acid?

Answer 9

DNA (deoxyribonucleic acid)
RNA (ribonucleic acid)

Question 10

what is the role of DNA

Answer 10

stores and transmits necessary info into cells to direct processes within the body

Question 11

what are three differences between prokaryotic and eukaryotic cells

Answer 11

• pro has circular DNA, euk has linear DNA
• pro has no nucleus, euk has nucleus
• pro has no membrane bound organelles, euk has membrane bound organelles

Question 12

what are histones?

Answer 12

Proteins that DNA is attached to

Question 13

state some differences between RNA and DNA

Answer 13

• RNA has ribose sugar, DNA has deoxyribose sugar
• RNA is single stranded, DNA is double stranded,
• RNA has the base Uracil, DNA has thymine

Question 14

what is the role of RNA?

Answer 14

TEMPORARILY store genetic material BEFORE cell division

Question 15

what is a chromatin

Answer 15

chromaTIN (tin of spaghetti) unstructured DNA

Question 16

what is the centre of a chromosome called

Answer 16

centromere

Question 17

what is a gene

Answer 17

a section of DNA

Question 18

what is the purpose of a gene

Answer 18

genes have uniqe base sequences that code for proteins.

Question 19

different genes have specific locations within DNA and chromosomes. what are these locations called?

Answer 19

locus

Question 20

what are the two parts of a chromosome that has split called

Answer 20

identical sister chromatids

Question 21

how many chromosomes do we have?

Answer 21

46, 23 pairs

Question 22

state the process of DNA REPLICATION/SEMI-CONSERVATIVE REPLICATION

Answer 22

• weak hydrogen bonds are broken by the enzyme helicase, and dna unwinds from double helix
• 2 single template strands are formed.
• free flowing DNA nucleotides are bound to their complementary bases that are exposed on the template strands, by the enzyme DNA polymerase
• new strand is synthesised in a 5 prime to 3 prime direction leading then lagging
• the enzyme ligase seals the sugar/phosphate back bone
• two DNA double helix’s are created. Each contains 1 new and 1 old DNA strand

Question 23

what are the three types of RNA

Answer 23

mRNA
rRNA
tRNA

Question 24

what is the role of mRNA

Answer 24

messenger RNA. transcribed from DNA and carries gene message out from nucleus to ribosome for translation into amino acid sequence.

Question 25

what is the role of rRNA

Answer 25

ribosomal RNA. makes up ribosome, assists with protein synthesis

Question 26

what is the role of tRNA

Answer 26

transfer RNA. carrier of specific amino acids (anti codon sequence that is complementary to codon on mRNA)

Question 27

what process follows these steps:
DNA –> RNA–> Protein.

Answer 27

protein synthesis

Question 28

what are the two processes involved in protein synthesis called?

Answer 28

transcription and translation

Question 29

where does transcription occur?

Answer 29

in the nucleus of eukaryotic cell

Question 30

what is the process of transcription?