unit 6

Question 1

what is DNA?

Answer 1

genetic code for traits

Question 2

DNA is made of long chains of…

Answer 2

nucleotides

Question 3

what are the three parts of a nucleotide?

Answer 3

-sugar
-phosphate
-nitrogenous base

Question 4

what are the 4 nitrogen bases (DNA)

Answer 4

-adenine
-thymine
-cytosine
-guanine

Question 5

what is a codon? what do they code for?

Answer 5

3 nitrogenous bases on mRNA coding for an amino acid

Question 6

explain the process of DNA replication

Answer 6

the unwinding of the double helix and separation of the DNA strands, the priming of the template strand, and the assembly of the new DNA segment

Question 7

helicase

Answer 7

the unzipping enzyme, breaks the hydrogen bonds between bases

Question 8

DNA polymerase

Answer 8

the builder, replicates DNA molecules

Question 9

primase

Answer 9

the initializer, makes the primer (made of RNA) that indicates where DNA polymerase should begin

Question 10

ligase

Answer 10

the gluer, glues DNA fragments together

Question 11

okazaki fragments

Answer 11

short sections of DNA formed at the time of discontinuous synthesis of the lagging strand during replication of DNA

Question 12

why is DNA replication considered to be “semi-conservative”?

Answer 12

when a DNA molecule replicates, each new double helix consists of one strand from the original DNA molecule and one newly synthesized strand, essentially “conserving” half of the original DNA molecule in each new copy

Question 13

replication fork

Answer 13

a Y-shaped region where the parent DNA double helix splits into two strands, subsequently copied

Question 14

leading strand

Answer 14

the strand that runs in the 5’ to 3’ direction towards the replication fork

Question 15

lagging strand

Answer 15

the strand that runs in the 5’ to 3’ direction away from the replication fork

Question 16

base pairs

Answer 16

two complementary nitrogenous bases that bond together to form the rungs of DNA’s double helix

Question 17

5’ to 3’

Answer 17

the direction in which new DNA is synthesized

Question 18

sugar in DNA and RNA

Answer 18

DNA: deoxyribose
RNA: ribose

Question 19

bases in DNA and RNA

Answer 19

DNA: adenine, thymine, cytosine, and guanine
RNA: adenine, uracil, cytosine, and guanine

Question 20

number of strands in DNA and RNA

Answer 20

DNA: 2
RNA: 1

Question 21

purpose of DNA and RNA

Answer 21

DNA: contains hereditary information
RNA: helps make protein

Question 22

mRNA

Answer 22

this RNA brings the information from the DNA about what the order of amino acids will be

Question 23

tRNA

Answer 23

this RNA collects amino acids and transfers them to the ribosome

Question 24

rRNA

Answer 24

this RNA makes up the parts of the ribosome that help build the proteins

Question 25

where in the cell does transcription take place?

Answer 25

nucleus

Question 26

where in the cell does translation take place?

Answer 26

ribosome

Question 27

what types of RNA are involved in transcription?

Answer 27

mRNA

Question 28

what types of RNA are involved in translation?

Answer 28

mRNA and tRNA

Question 29

what is the purpose of transcription?

Answer 29

make mRNA

Question 30

what is the purpose of translation?

Answer 30

make a protein

Question 31

the creation of mRNA, or mRNA synthesis, occurs during...

Answer 31

transcription

Question 32

the creation of proteins, or protein synthesis, occurs during...

Answer 32

translation

Question 33

what is a mutation?

Answer 33

permanent change in nucleotide/DNA sequence

Question 34

what can cause a mutation?

Answer 34

errors during DNA replication during cell division, exposure to environmental factors like radiation, smoking or certain chemicals, viral infections, or even spontaneous occurrences within the cell itself

Question 35

frameshift mutation

Answer 35

if there's an addition (insertion) or deletion of extra nucleotides of DNA

Question 36

point mutation

Answer 36

if a single nucleotide is changed or substituted

Question 37

silent point mutation

Answer 37

when the new codon codes for the same amino acid

Question 38

missense point mutation

Answer 38

conservative missense: the new codon codes for a different amino acid that works similar to the original amino acid non conservative missense: the new codon codes from a different amino acid that works differently from the original amino acid

Question 39

nonsense point mutation

Answer 39

when the new codon codes for a stop codon

Question 40

insertion mutation

Answer 40

when an additional base is added to the nucleotide sequence

Question 41

deletion mutation

Answer 41

when a base is removed from the nucleotide sequence

Question 42

what does epigenetics do to our DNA?

Answer 42

epigenetics is when environmental factors influence which genes are expressed. methyl groups attach the DNA causing it to wrap around histones more tightly, making it so those genes cannot be read or expressed. this process is called methylation. these methyl tags can be passed on through generations.

Question 43

mutagen

Answer 43

in genetics, a mutagen is a physical or chemical agent that permanently changes genetic material, usually DNA, in an organism and thus increases the frequency of mutations above the natural background level