Chapter 16 & 17

Question 1

What are the monomers and polymers of nucleic acids?

Answer 1

Monomer: nucleotide
Polymer: polynucleotide

Question 2

What are the 3 components of a nucleotide?

Answer 2

• 5 carbon sugar
• Phosphate group (negatively charged)
• Nitrogenous base

Question 3

What is the sugar in DNA?

Answer 3

Deoxyribose

Question 4

What is the sugar in RNA?

Answer 4

Ribose

Question 5

What is the structure of DNA?

Answer 5

Double stranded (double helix)

Question 6

What is the structure of RNA?

Answer 6

Single-stranded

Question 7

Where is DNA found?

Answer 7

Always in the nucleus
(Extra types: mDNA in mitochondria, cDNA in chloroplasts)

Question 8

Where is RNA made and where does it function?

Answer 8

Made: nucleus
Functions: cytoplasm

Question 9

What is the function of DNA?

Answer 9

Contains instructions to make all proteins needed for survival

Question 10

What is the function of RNA?

Answer 10

Organizes and participates in protein synthesis

Question 11

What are the nitrogenous bases in DNA?

Answer 11

A, T, C, G

Question 12

What are the nitrogenous bases in RNA?

Answer 12

A, U, C, G

Question 13

Which nitrogen bases are pyrimidines?

Answer 13

Cytosine, Thymine, Uracil (single ring)

Question 14

Which nitrogen bases are purines?

Answer 14

Adenine, Guanine (double ring)

Question 15

What holds polynucleotide strands together?

Answer 15

Hydrogen bonds

Question 16

Why are hydrogen bonds important?

Answer 16

They are easily broken, allowing DNA to open and be read

Question 17

What does antiparallel mean?

Answer 17

DNA strands run opposite directions (5’→3’ and 3’→5’)

Question 18

What are the complementary base pairs in DNA?

Answer 18

A ↔ T (2 hydrogen bonds)

G ↔ C (3 hydrogen bonds)

Question 19

Complementary strand to 5’ ATCGGT 3’?

Answer 19

3’ TAGCCA 5’

Question 20

What do histone proteins do?

Answer 20

DNA wraps around them for packaging

Question 21

What is chromatin?

Answer 21

Loosely condensed DNA

Question 22

What is a chromosome?

Answer 22

Maximally compacted DNA

Question 23

What is mRNA?

Answer 23

Straight chain

Contains info to make one protein

Uses codons

Question 24

What is a codon?

Answer 24

3 nucleotides on mRNA that code for an amino acid

Question 25

What is tRNA?

Answer 25

Folded RNA Transfers amino acids to ribosome Has an amino acid on top Has an anticodon on bottom

Question 26

What is an anticodon?

Answer 26

3 bases on tRNA complementary to an mRNA codon

Question 27

When does protein synthesis occur?

Answer 27

When codon and anticodon match

Question 28

What is rRNA?

Answer 28

Ribosomal RNA that forms large + small ribosomal subunits

Question 29

What is transcription?

Answer 29

Creating RNA from DNA (in nucleus)

Question 30

What is translation?

Answer 30

Creating proteins from mRNA

Question 31

What is a DNA triplet?

Answer 31

3 bases on DNA

Question 32

What is a codon?

Answer 32

3 bases on mRNA

Question 33

Steps of transcription (in order)

Answer 33

1. RNA polymerase binds to promoter (upstream) 2. Binds to 3’ end of template strand 3. Adds complementary RNA nucleotides 4. Stop sequence causes release of mRNA

Question 34

What does RNA polymerase do?

Answer 34

Builds the mRNA strand

Question 35

Which DNA strand does mRNA resemble?

Answer 35

Coding strand (except U replaces T)

Question 36

What is splicing?

Answer 36

Removing noncoding sequences from mRNA

Question 37

What are introns?

Answer 37

Noncoding segments removed from the transcript

Question 38

What are exons?

Answer 38

Expressed/coding sequences kept in mRNA