Unit 2: Lecture 1

Question 1

What is a genome?

Answer 1

all of the genetic material, USUALLY DNA, transmitted from parent to offspring

Question 2

What does a haploid human genome contain?

Answer 2

23 chromosomes

Question 3

What is a diploid human genome?

Answer 3

maternal copy and paternal copy of chromosomes, plus mitochondrial DNA

Question 4

Is the genome entirely contained in the nucleus?

Answer 4

no

Question 5

Compare chromosomal structure in bacterial vs. eukaryotic cells.

chromosome
cell
DNA

Answer 5

bacterial
chromosome: circular
cell: haploid
DNA: double-stranded

eukaryotic
chromosome: linear
cell: diploid
DNA: double-stranded

Question 6

What is a haploid cell?

Answer 6

contains one set of chromosomes

Question 7

What is a diploid cell?

Answer 7

contains two sets of chromosomes (one maternal, one paternal)

Question 8

How is DNA packaged in bacterial cells?

Answer 8

all DNA in the cell is tightly wound (supercoiled)

Question 9

What is genome size?

Answer 9

number of base pairs

genome size is small, then cells are small

Question 10

What is a bacterial nucleoid?

Answer 10

the bacterial chromosome twists on itself to form supercoils, which are anchored by proteins

Question 11

How is DNA packaged in eukaryotes?

Answer 11

DNA is wound around proteins called histones and wound into chromatin

when cells divide in mitosis or meiosis, the chromatin is further wound into the chromosome

Question 12

What does each chromatid have?

Answer 12

one long piece of DNA double helix wrapped up

Question 13

each chromosome has two chromatids before the cell divides

Answer 13

• 23 pairs of homologous chromosomes (one chromosome in pair from mother, one from father)
• 46 chromosomes with two chromatids prior to mitosis
• 92 double DNA helices
• if you heated the DNA to separate the strands of the double helix, there would be total 184 DNA individual strands

Question 14

What is one eukaryotic chromatid equal to?

Answer 14

one linear DNA double helix

Question 15

What is one eukaryotic chromosome equal to?

Answer 15

two chromatids

Question 16

What is a phenotype?

Answer 16

observable characteristics and traits

Question 17

What is a genotype?

Answer 17

genetic make-up of a cell or organism, the sequence of the DNA

Question 18

What is a gene?

Answer 18

unit of hereditary information consisting of a DNA sequence

Question 19

What is the sequence of genes?

Answer 19

a sequence of bases in a region of the DNA that can code for a protein (via mRNA) or RNA (tRNA or rRNA)

Question 20

Describe the relationship between genotype and phenotype.

Answer 20

genotype is DNA sequence in on or more genes that encode proteins whose function determines traits

Question 21

What are the bonds or interactions between bases?

Answer 21

hydrogen bonds

Question 22

What is the backbone of DNA made of?

Answer 22

two strands: one phosphate and one sugar

Question 23

What type of interactions are hydrogen bonds?

Answer 23

intermolecular

Question 24

What tends to have similar genomes?

Answer 24

prokaryotes

Question 25

Describe the sequence composition of the human genome?

Answer 25

genomes contain both coding and non-coding regions of DNA

only a portion of the human genome codes for proteins

Question 26

What kind of chromosomes are in bacterial cells?

Answer 26

circular

Question 27

What kind of chromosomes are in human cells?

Answer 27

linear

Question 28

What kind of cells are in bacterial cells?

Answer 28

haploid

Question 29

What kind of cells are in human cells?

Answer 29

diploid