Final exam material

Question 1

Homozygous

Answer 1

both alleles are the same (either recessive or dominant)

Question 2

Heterozygous

Answer 2

Both alleles are different (dominant and recessive)

Question 3

Incomplete dominance

Answer 3

Neither allele is fully dominant, both MIX together
White + black = gray

Question 4

Codominance

Answer 4

Both alleles are expressed and can be noticed
White + black = black and white speckled fur

Question 5

Polygenic inheritance

Answer 5

inheritance based upon multiple genes

Question 6

Sex linked inheritance

Answer 6

Certain genes are only found on the X or Y chromosome

*note that girls get an X from both their father and mother
Boys get a Y from dad and X from mom

Question 7

Linked genes

Answer 7

Genes that aren’t likely to separate during crossing over as they are close together on the chromosome

Question 8

Epistasis or gene masking

Answer 8

Expression of one gene mask the expression of another
Ex. gene that makes people bald mask the expression of hair color

Question 9

Semiconservative DNA replication

Answer 9

each daughter cell receives one old strand and one new strand
*this one is the one that actually happens

Question 10

Purines

Answer 10

Larger double ring structure
Adenine and guanine

Question 11

Pyrimidines

Answer 11

Smaller single ring structure

Thymine and cytosine

Question 12

DNA structure

Answer 12

Sugar phosphate backbone held together by phosphate diester bonds

Nitrogenous bases (ATGC) bond together in the middle with hydrogen bonds

Question 13

Replication bubble

Answer 13

site on DNA where DNA splits so it may be replicated

Question 14

Helicase

Answer 14

enzyme that splits the hydrogen bonds of nitrogenous bases in order to separate DNA

Question 15

Primase

Answer 15

enzymes that synthesis primers (short RNA sequences that create a starting point for DNA synthesis)

*DNA polymerase III can only add to existing three strands, that’s why this is necessary

Question 16

How are Okazaki fragments made

Answer 16

The lagging strand of DNA synthesizes away from the replication fork, this means that the template DNA will be unwound behind the current primer necessitating the need for a new one, creating another Okazaki fragment

Question 17

Energy transmission in adding nucleotides

Answer 17

cleaves the phosphodiester bond on the three end of the existing nucleotide and uses that to add it to the newly attached nucleotides

Question 18

Topoisomerase

Answer 18

responsible for relieving the tension on the DNA strand at the replication bubble by cutting the DNA strands

Question 19

Point mutations

Answer 19

affect one or small number of base pairs

Question 20

Silent mutation

Answer 20

The RNA sequence still codes for the same string of amino acids as the non mutated version

Question 21

non-sense mutation

Answer 21

addition of a point mutation leads to a premature stop coding usually making the protein unfunctional

Question 22

frame-shift

Answer 22

addition or subtraction of nucleotides into the DNA sequence, leading to the current nucleotides to shift over a particular number

Question 23

break down transcription

Answer 23

1.RNA polymerase binds to promoter sequence (specific DNA sequence that signals where polymerase should bind)

2. adds corresponding RNA nucleotides
3. reaches stop sequence

Question 24

Differences in transcription between prokaryotes and eukaryotes

Answer 24

in prokaryotes, the sigma protein recognizes the promoter and helps RNA polymerase bind, in eukaryotes they use transcription factors

3 versions of RNA polymerase vs 1 in prokaryotes

*note that during transcription, prokaryotes can start translating the mRNA while eukaryotes do not posses this ability

Question 25

introns and exons

Answer 25

exons are the sequences that are translated into proteins Introns are the sequences in the middle that aren't included during RNA splicing *this allows for alternative splicing(different proteins made from the same DNA sequence) as certain exons can be left out

Question 26

describe initiation of RNA translation (protein synthesis)

Answer 26

small sub unit connects to mRNA strand start codon on this strand binds to one end of tRNA larger subunit the binds to other end of tRNA

Question 27

Repressor proteins

Answer 27

type of protein that binds to DNA to halt transcription

Question 28

Activator proteins

Answer 28

type of protein that binds to DNA to start transcription

Question 29

Operons

Answer 29

multiple genes located close together on bacterial DNA that code for functionally related protiens but are controlled by the same promoter

Question 30

Operators

Answer 30

DNA sequences in front of a protein coding gene sequence repressor proteins can then bind to the operator sequence, halting translation of a certain gene

Question 31

Methyl groups effect on DNA

Answer 31

triggers chromatin condensation making DNA less accessible

Question 32

Acetyl groups effect on DNA

Answer 32

triggers chromatin decondensation making DNA more accessible

Question 33

Apoptosis

Answer 33

programmed cell death *ex. neurons that don't establish connections early on will die

Question 34

Ligase

Answer 34

In the context of DNA, ligase connects nucleotides with phosphodiester bonds *important during DNA replication

Question 35

why are the poly(A) tail and 5' cap needed on mRNA

Answer 35

prevents the mRNA from being degraded by enzymes

Question 36

-35 and -10 boxes

Answer 36

found in prokaryotic cells, sigma protien uses it as the marker for where it should help RNA polymerase bind

Question 37

telomerase

Answer 37

Adds DNA to end of telomeres lengthening the chromosomes, this extends the lifespan of the cell and how many times it can divide

Question 38

Codon

Answer 38

triplet of nucleotides that code for specific amino acid

Question 39

Why do cells need to regulate protein production

Answer 39

energy efficiency Amount of certain protein is needed at different times in development different amounts of the same protein are needed for different cells(multicellular) adjusting to a changing environment