Chapter 1

Question 1

What is a phenotype?

Answer 1

the observable traits of an organism

Question 2

What is a genotype?

Answer 2

the genetic constitution of an organism

Question 3

What is genetic variation?

Answer 3

differences between alleles/in nucleotide sequence

Question 4

What is an allele?

Answer 4

alternative forms of a gene

Question 5

What is the Law of Segregation?

Answer 5

Mendel’s contribution that only one of the two gene copies present in an organism is distributed to each gamete (egg or sperm cell) that it makes, and the allocation of the gene copies is random

Question 6

What is the Law of Independent Assortment?

Answer 6

In Meiosis, when the alleles at separate genes on different chromosomes segregate and sort independently

Question 7

What are genes?

Answer 7

the physical units of heredity, as originally posited by Mendel; now known to be defined DNA sequences

Question 8

What are chromosomes?

Answer 8

long molecules of double-stranded DNA wrapped around proteins, which contains genes

Question 9

What do sexually reproducing organisms usually have?

Answer 9

homologous pairs(or homologs), two of each chromosome, where one homolog comes from each parent

Question 10

what is produced by meiosis?

Answer 10

reproductive cells, or gametes

Question 11

What are the 3 domains of life?

Answer 11

1. Eukarya (true nucleus, multiple chromosomes)
2. Bacteria (no true nucleus, single chromosomes)
3. Archaea (no true nucleus, single chromosomes)

Question 12

What are 5 characteristics of eukaryotic cells?

Answer 12

1. multiple chromosomes organized by proteins
2. membrane-bound nucleus and intracellular membrane
3. membrane-bound organelles
4. unicellular and multicellular
5. larger genomes

Question 13

What are 4 characteristics of prokaryotic cells?

Answer 13

1. single large chromosome(some also contain plasmids)
2. no membrane-bound nucleus or cellular membranes
3. unicellular
4. smaller genomes

Question 14

What type of cells contain mitochondria?

Answer 14

plant and animal cells

Question 15

What type of cells contain chloroplasts?

Answer 15

plant cells

Question 16

What is the structure of DNA?

Answer 16

double helix with sugar phosphate backbones on the outsides and nucleotide bases arrayed in complementary pairs toward the center

Question 17

What are DNA Nucleotides composed of?

Answer 17

a deoxyribose(5-carbon) sugar, a phosphate group, and one of 4 nitrogenous bases designated-Adenine, Guanine, Thymine, Cytosine

Question 18

How are nucleotides linked together?

Answer 18

linked together by a phosphodiester bond between the 5’ phosphate group of one nucleotide and the 3’ hydroxyl of another

Question 19

What kind of bond forms between complementary base pairs?

Answer 19

hydrogen bonds

Question 20

What is a characteristic of the two strands of DNA?

Answer 20

they are antiparallel, meaning that the 5’ and 3’ designations of the phosphate and hydroxyl at the ends of the DNA strands establish polarity

Question 21

What number does meiosis start and end with?

Answer 21

starts with diploid number and ends in gametes with the haploid number of chromosomes(4 distinct gametes produced)

Question 22

What is Chargaff’s rule?

Answer 22

for most organisms the percentage of adenine and thymine are equal, and the percentage of guanine and cytosine are equal