Chapter 4: Heredity & Disease

Question 1

What does DNA stand for

Answer 1

deoxy-ribo-nucleic acid

Question 2

what shape is DNA

Answer 2

a double helix

Question 3

what is DNA made up of

Answer 3

1. Deoxyribose sugar
2. Phosphate
3. Nucleotide Bases

Question 4

gene

Answer 4

a segment of DNA that codes for a particular protein

Question 5

chromosome

Answer 5

DNA tightly packaged with proteins

Question 6

how many pairs of chromosomes in a human are autosomes

Answer 6

44 chromosomes (or 22 pairs)

Question 7

sex chromosomes

Answer 7

2 chromosomes in a human.
XX is female
XY is male

Question 8

karyotype

Answer 8

a visualization of an organisms complete set of chromosomes arranged by size

Question 9

what does meiosis do?

Answer 9

the process of the separation of chromosome pairs

Question 10

how many parts of meiosis are there

Answer 10

two

Question 11

mutations

Answer 11

mistakes during replication (meiosis)

lead to abnormal chromosome numbers

cell may possibly fix itself

Question 12

what makes a diploid embryo

Answer 12

haploid egg + haploid sperm

Question 13

crossing over

Answer 13

an exchange of genetic material between a pair of chromosomes

Question 14

ploidy

Answer 14

number of sets of homologous chromosomes occuring in a cell

Question 15

diploid

Answer 15

• 2n
• 2 sets: 1 from mother, 1 from father
• somatic cells

Question 16

haploid

Answer 16

• n
• gametes
• 1 set

Question 17

alleles

Answer 17

alternate forms of a gene

Question 18

homozygous

Answer 18

2 alleles of the gene are the same

Question 19

heterozygous

Answer 19

2 alleles of the gene that are different

Question 20

dominant trait

Answer 20

only 1 copy of an allele is needed to cause the trait

• co-dominance (AB blood)

Question 21

recessive trait

Answer 21

2 copies of an allele needed to cause the trait (must be homozygous to appear)

Question 22

genome

Answer 22

the complete set of DNA in an organism

Question 23

hereditary diseases

Answer 23

defective genes make defective protein(s) OR no proteins

Question 24

multifactoral traits

Answer 24

traits that result from the action of several genes

-environmental likely to contribute as well

Question 25

autosomal dominant disorders

Answer 25

• disease tends to appear in every generation of the family
• males & females affected
• not a sex chromosome
• 1 copy of defective allele