Ch 4- Genetics

Question 1

What is the function of DNA?

Answer 1

to store all the genetic information an organism needs

Question 2

Base pairs DNA

Answer 2

Guanine-Cytosine

Adenine- Thymine

Question 3

gene

Answer 3

part of DNA that determines a characteristic of a the offspring

Question 4

chromosome

Answer 4

chromatin strings of DNA wrapped around histones which create a chromosome
-replicate DNA

Question 5

what is the purpose of DNA replication?

Answer 5

to produce 2 identical copies of a DNA strand

Question 6

what are the three main steps of dna replication?

Answer 6

1. helicase unwinds dna in the 5’ to 3’ direction
2. Primase adds primer to both ends
3. Builds 5’ to 3’, lagging strand builds in chunks
4. Ligase glues together and fills in gaps

Question 7

why does our bodies need to make proteins?

Answer 7

to build and repair tissues, it’s our building block

Question 8

what is the central dogma of molecular biology?

Answer 8

Dna-> Rna -> protein -> trait

Question 9

Purpose of transcription

Answer 9

• converts DNA to Mrna (by rna polymerase)

- genetic info is carried to ribosome

Question 10

purpose of translation

Answer 10

-genetic mrna code is used to produce a sequence of amino acids which will become a protein

Question 11

introns and exons

Answer 11

introns-junk, dont code for proteins

exons- code for proteins

Question 12

what is the purpose of mitosis?

Answer 12

cell regeneration, growth, and asexual reproduction

Question 13

mitosis/meiosis differences

Answer 13

mitosis- regenerates cells

meiosis- creates sex cells

Question 14

what is the difference between interphase and mitosis?

Answer 14

interphase- cell is preparing for division (G1, S, G2)

mitosis- cell splits

Question 15

purpose of meiosis?

Answer 15

to create sex cells

Question 16

haploid/diploid definitions

Answer 16

haploid- single set of chromosomes

diploid- 2 complete sets of chromosomes from each parent

Question 17

Gel electrophoresis

Answer 17

• DNA fragments + -> -
• DNA is negative
• restriction enzymes cut up fragments of dna and help identify a person because everyone has different restriction enzymes
• smaller fragments move faster through gel

Question 18

examples of biotechnology

Answer 18

PCR, DNA isolation, karotyping

Question 19

gene mutation

Answer 19

permanent change to the DNA of a gene

Question 20

chromosome mutation

Answer 20

permanent change in the structure of chromosomes in the cell
ex: down syndrome

Question 21

types of mutations: which is the most harmful?

Answer 21

1-substitution
2- insertion
3- deletion

2+3 are the worst

Question 22

causes of mutation

Answer 22

caused by mutagens

affects: transcription, replication of DNA, chromosomal breakage
- DNA strand breakage

Question 23

dominant trait

Answer 23

when one trait overpowers the other

Question 24

recessive trait

Answer 24

the trait this is hidden/masked

Question 25

genotype

Answer 25

how the two alleles are written on the gene (ex: Bb)

Question 26

phenotype

Answer 26

the physical appearance of the trait

Question 27

homozygous

Answer 27

2 of the same alleles (TT, tt)

Question 28

heterozygous

Answer 28

two different alleles (Tt)

Question 29

Complete dominance

Answer 29

when a genotype is heterozygous, it takes the trait of the dominant allele

Question 30

incomplete dominance

Answer 30

when the heterozygous phenotype is an intermediate/mixture between the two homeozygous phenotypes

Question 31

co-dominance

Answer 31

when the heterozygous phenotype contains both phenotypes (ex: brown with white spots)

Question 32

what is the purpose of a pedigree?

Answer 32

to show how a trait is inherited over several generations