Science Exam Poo

Question 1

What makes up a nucleotide

Answer 1

A nitrogenous base, a sugar (ribose or deixyribose), and a phosphate group

Question 2

What is chargoffs rule

Answer 2

The total number of purines (A and G) is equal to the total number of pyrimidines

Question 3

What did meischer do

Answer 3

First person to observe DNA, broke down nuclei of wbc and found grey substance called nuclein

Question 4

What did Levene do

Answer 4

Discovered what nucleotides are made of and made DNA model formed of polynucleotide chains

Question 5

What did chargoff do

Answer 5

Discovered that there is the same number of purines as pyrimidines

Question 6

What did Franklin do

Answer 6

Produced first image of DNA using x-ray crystallography to show DNAs diffraction pattern

Question 7

What did Watson and crick do

Answer 7

Researching DNAs 3D shape, stole Franklin’s image and published a paper about the double helix, awarded Nobel prize

Question 8

What enzymes are involved in DNA replication

Answer 8

Helicase, primase, DNA polymerase III, DNA polymerase I, ligase

Question 9

Helicase

Answer 9

Unzips DNA

Question 10

Primase

Answer 10

Lays down primer so DNA polymerase III can build nucleotides

Question 11

DNA polymerase III

Answer 11

Adds nucleotides to create new DNA strand

Question 12

DNA polymerase I

Answer 12

Replaces RNA primers with nucleotides

Question 13

Ligase

Answer 13

Repairs breaks in sugar-phosphate backbone

Question 14

Okazaki fragments

Answer 14

DNA fragments that are not fully attached to the strand

Question 15

Transcription

Answer 15

Happens in nucleus, Helicase unzips DNA, RNA polymerase attaches to a promoter and adds complementary mRNA nucleotides, mRNA leaves through nuclear pore

Question 16

Translation

Answer 16

Happens in cytoplasm, mRNA attaches to ribosome, ribosome lines up complementary tRNA molecules (tRNA anticodons must match mRNA codons), amino acids form peptide bonds and build a polypeptide strand, tRNA detach from amino acids and leave to pick up more

Question 17

What is the start codon and what does it do

Answer 17

AUG, Signals when to begin translation

Question 18

What are the stop codons and what do they do

Answer 18

UGA, UAA, and UAG, Signal when to stop translation

Question 19

Antiparrallel

Answer 19

The DNA strands run in opposite directions parallel to each other

Question 20

What are the types of chromosomal mutations

Answer 20

Duplication, deletion, inversion, translocation

Question 21

Duplication (C)

Answer 21

Extra copy of genes are added to chromosome

Question 22

Deletion (C)

Answer 22

A piece id the chromosome breaks off and is lost

Question 23

Inversion (C)

Answer 23

A Segment of the chromosome gets reversed

Question 24

Translocation (C)

Answer 24

A piece of one chromosome breaks off and attaches to another

Question 25

What is a frame shift mutation

Answer 25

Shifts the “reading frame” of mRNA codons forwards or backwards changing the amino acid sequence (insertion/deletion)

Question 26

What is substitution/point mutation

Answer 26

When one nucleotides base is substituted for another

Question 27

What is insertion

Answer 27

When one or more bases are inserted into the DNA making the strand longer

Question 28

What is deletion

Answer 28

When one or more bases are deleted from the DNA making the strand shorter

Question 29

Difference between frame shift mutations and point mutations

Answer 29

Frameshift: adds or subtracts bases, effects everything after the mutation point Point: changes one base, only effects where base is changed

Question 30

Silent mutation

Answer 30

Has no effect on amino acid coded for since many amino acids are coded for by many codons

Question 31

Missense mutation

Answer 31

Causes codon to code for different amino acid than original

Question 32

Nonsense mutation

Answer 32

Causes a stop codon that terminates translation early and often results in nonfunctional protein

Question 33

How can mutation produce variation in a population and what does that mean

Answer 33

Mutations can give people different traits, looks, etc, mutations/alleles make everyone unique

Question 34

What is one positive example of a mutation

Answer 34

HbAS, a mutation that causes both normal and sickled cells, provides resistance to malaria

Question 35

What is one negative example of a mutation

Answer 35

HbSS mutation causes sickled RBCs, resulting in sickle cell disease

Question 36

Leading strand vs lagging strand

Answer 36

Leading: built continuously, 5’ to 3’ Lagging: built in Okazaki fragments, 3’ to 5’

Question 37

What is something that causes a mutation called

Answer 37

Mutagen

Question 38

Where is DNA found in eukaryotes

Answer 38

The nucleus

Question 39

When does DNA replication occur

Answer 39

Interphase

Question 40

Almost all errors that are detected are fixed by

Answer 40

DNA polymerase

Question 41

What organelle helps form proteins

Answer 41

Ribosome

Question 42

What are the types of RNA

Answer 42

Transfer, Messenger, ribosomal

Question 43

tRNA

Answer 43

Brings amino acids to ribosome

Question 44

rRNA

Answer 44

Makes up ribosome, helps bind amino acids

Question 45

What is another name for a polypeptide

Answer 45

Protein

Question 46

What part of a DNA molecule Ike is referred to as the code

Answer 46

Nucleotides

Question 47

Insertion/deletion changes…

Answer 47

The protein produces by the gene

Question 48

What binds are formed between base pairs

Answer 48

Hydrogen