Chapter 9 - DNA

Question 1

Acetylation

Answer 1

Addition of an acetyl group to a histone protein - gene expression is enhanced

Question 2

Adenine

Answer 2

Nitrogenous base found in DNA and RNA

Question 3

Anticodon - ensures

Answer 3

Anticodon on a tRNA molecule is made of 3 nucleotides. It is complementary to a specific codon on the mRNA molecule. Ensures tRNA molecule carries the amino acid that aligns with specific codon.

Question 4

Chromatin

Answer 4

Tangled network of DNA in nucleus of cell that is not dividing.

Question 5

Chromosome

Answer 5

One of 46 rod like structures that appear in nucleus of somatic cell at commencement of cell division

Question 6

Coding strand

Answer 6

Strand of DNA molecule that is not used to form mRNA. The mRNA molecule will match the base sequence on the coding strand with Thymine replaced with Uracil.

Question 7

Codon

Answer 7

Sequence of three nucleotides in mRNA

Question 8

Cytosine

Answer 8

Nitrogenous base found in DNA and RNA

Question 9

Guanine

Answer 9

Nitrogenous base found in DNA and RNA

Question 10

Thymine

Answer 10

Nitrogenous base found in DNA. Replaced with Uracil in RNA in DNA replication

Question 11

Uracil

Answer 11

Nitrogenous base found in RNA

Question 12

DNA - determines

Answer 12

Molecule in the nucleus of a cell - determines what proteins a cell can make

Question 13

DNA ligase

Answer 13

Enzyme that joins short sections of DNA together

Question 14

DNA polymerase

Answer 14

Enzyme that joins nucleotides together in nuclear replication

Question 15

DNA replication

Answer 15

Production of an identical copy of the DNA

Question 16

Double helix

Answer 16

Spiral shape of the DNA molecule

Question 17

Epigenetics

Answer 17

Altering the expression of a gene without changing the gene structure

Question 18

Gene

Answer 18

Section of a chromosome that contains the nucleotide sequence, coding for a particular trait

Question 19

Gene expression

Answer 19

Process where the information in a gene is used to make a product

Question 20

Histone

Answer 20

Protein which DNA is coiled around to from chromatin

Question 20

Helicase

Answer 20

Enzyme responsible for separation of DNA strand during replication

Question 21

mRNA

Answer 21

Messenger RNA. Transfers coded information from the nucleus to the ribosomes

Question 22

Methylation

Answer 22

Addition of a methyl group to a cytosine base on DNA molecule that results in decreased transcription

Question 23

mtDNA

Answer 23

Mitochondrial DNA

Question 24

Nucleosome

Answer 24

Length of DNA wound around 8 histone proteins, forms chromatin

Question 25

Nucleotide

Answer 25

Unit of phosphate, sugar and nitrogen base that mak eup the DNA molecule

Question 26

RNA

Answer 26

Ribonucleic acid. Molecule that takes code for amino acids from DNA to the ribosomes

Question 27

RNA polymerase

Answer 27

Active enzyme during transcription of RNA from DNAS

Question 28

Start codon

Answer 28

Sequence AUG (methionine), when ribosome reaches codon it starts making protein

Question 29

Template strand

Answer 29

Strand of DNA that is used to form the sequence of bases in mRNA.

Question 30

Transcription

Answer 30

Process which mRNA is formed by complementary sequence of nucleotides

Question 31

tRNA

Answer 31

Transfer RNA. Molecule brings amino acids from the cytoplasm to the ribosome

Question 32

Translation (protein synthesis)

Answer 32

Production of a protein using the information coded in the mRNA.

Question 33

Base triplet

Answer 33

Sequence of three bases that is the code for a particular amino acid.

Question 34

epigenetic factors

Answer 34

external factors that can modify gene expression through methylation and acetylation

Question 35

Deacetylation

Answer 35

acetyl group is removed from histone tail. some genes require presence of acetyl groups for their transcription - means gene expression is inhibited.

Question 36

epigenetic tags

Answer 36

small molecules that attach to DNA to make it easier/harder for translation of a gene to occur. Can also switch genes off

Question 37

promotor sequence

Answer 37

binding site on DNA that initiates the process of transcription by signaling where transcription of a gene should begin

Question 38

terminating sequence

Answer 38

end of a gene in DNA is marked by a terminating sequence. it instructs the RNA polymerase to stop transcribing DNA to RNA, marks the end of the gene that is being synthesised