8.1 & 8.2: Genes and the triplet code & DNA and chromosomes

Question 1

Eukaryotic DNA

chromosomes

Answer 1

long, linear chromosomes made up of DNA
chromosomes are in the nucleus
the dna molecule is wound up so it fits as its really long

Question 2

Histones

Answer 2

proteins which the DNA molecule winds around and support the the DNA

Question 3

Compact chromosome made by

Answer 3

the DNA and histone coiled up very tightly

Question 4

Mitochondria and chloroplasts have

Answer 4

their own DNA which is circular and shorter and fits in the cell by supercoiling

Question 5

Genes

Answer 5

a gene is a sequence of DNA bases that codes for a polypeptide or functional RNA

Question 6

What determines the order of amino acids in a polypeptide

Answer 6

the order of bases in a gene

Question 7

Triplet

Answer 7

a sequence of 3 bases in a gene which code for am amino acid

Question 8

Functional RNA

Answer 8

performs specific tasks during protein synthesis

eg: tRNA and rRNA

Question 9

rRNA

Answer 9

ribosomal RNA forms parts of ribosomes

Question 10

Introns

Answer 10

sections of genes that don’t code for amino acids and are not useful

Question 11

Exons

Answer 11

sections of genes that do code for amino acids

Question 12

Multiple repeats

Answer 12

sections of DNA that repeat ‘over and over’ outside of genes and they don’t code for amino acids either

Question 13

Non- coding repeats

Answer 13

another name for multiple repeats

Question 14

Alleles are a

Answer 14

gene existing in another form

Question 15

Alleles

order of bases

Answer 15

The order of bases in each allele is slightly different so they code for different versions of the same polypeptide

Question 16

Homologous pair

Answer 16

pair of matching chromosomes which are the same size and have the same genes but could have different alleles

Question 17

Locus

Answer 17

alleles coding for the same characteristic will be found at the same FIXED POSITION (locus) on each chromosome in a homologous pair