DNA, Chromosomes and Genes

Question 1

define chromosome

Answer 1

the structure DNA is packaged into in eukaryotic cells, DNA is wound around proteins called histones

Question 2

define homologous chromosome

Answer 2

each chromosome is one of a pair of chromosomes (one maternal, one paternal) that have the same genes at the same loci (locations) but may be alleles

Question 3

define gene

Answer 3

sequence of DNA bases that codes for a specific polypeptide chain

Question 4

define allele

Answer 4

an alternative version of a gene

Question 5

define locus

Answer 5

the position of a gene on a chromosome

Question 6

define intron

Answer 6

non-coding regions of DNA within a gene

Question 7

define exon

Answer 7

coding regions of DNA within a gene

Question 8

compare the structural shape of eukaryotic DNA, prokaryotic DNA and DNA in chloroplasts and mitochondria

Answer 8

eukaryotes: linear
prokaryotes + chloroplasts + mitochondria: circular

Question 9

compare the length of the DNA strand in eukaryotic DNA, prokaryotic DNA and DNA in chloroplasts and mitochondria

Answer 9

eukaryotes: longer
prokaryotes + chloroplasts + mitochondria: shorter

Question 10

compare how DNA is packages in eukaryotes, prokaryotes, chloroplasts and mitochondria

Answer 10

eukaryotes: DNA is wrapped around histone proteins and packaged into chromosomes
prokaryotes + chloroplasts + mitochondria: DNA is not wrapped around histone proteins and is not packaged into chromosomes

Question 11

compare what genes include in eukaryotes, prokaryotes, chloroplasts and mitochondria

Answer 11

eukaryotes: genes include both introns and exons
prokaryotes + chloroplasts + mitochondria: genes only include exons

Question 12

define what is means for a triplet code to be degenerate

Answer 12

each amino acid is coded for by more than one triplet code

Question 13

define punctuated in terms of genetic code

Answer 13

there are stop and start triplets to signal beginning and end of transcription and translation