Unit 2 - Genetics

Question 1

what are genes?

Answer 1

sections of dna that contain genetic information for the inheritance of specific traits

Question 2

what is the structure of dna?

Answer 2

dna is made up of two long strands that form a spiral shape called a double helix

Question 3

what are the two components of the “back bone” in dna

Answer 3

1. phosphate

2. sugar

Question 4

what are the four different bases of the monomers (nucleotides) in dna?

Answer 4

1. adenine
2. guanine
3. cytosine
4. thymine

Question 5

what are the two different types of molecules of these two bases?

Answer 5

purines and pyrimides

Question 6

how many rings does purines and pyrimids have in their structure?

Answer 6

purines have two rings

pyrimides have one ring

Question 7

what are the two bases that are purines?

Answer 7

adenine

guanine

Question 8

what are the two bases that are pyrimids?

Answer 8

thymine

cytosine

Question 9

reproductive cells are called?

Answer 9

gametes

Question 10

the cell that results from reproductive cells is called?

Answer 10

zygote

Question 11

each human gamete is haploid with how many cells?

Answer 11

23

Question 12

what is a non disjunction disorder?

Answer 12

There are three forms of nondisjunction: failure of a pair of homologous chromosomes to separate in meiosis I, failure of sister chromatids to separate during meiosis II, and failure of sister chromatids to separate during mitosis. Nondisjunction results in daughter cells with abnormal chromosome numbers

Question 13

what is a dominant vs recessive trait?

Answer 13

For a recessive allele to produce a recessive phenotype, the individual must have two copies, one from each parent. An individual with one dominant and one recessive allele for a gene will have the dominant phenotype.