Test 3 Chapter 10 Study Guide

Question 1

Transformation

Answer 1

Horizontal gene transfer using “naked” DNA - I.E. DNA in the environment

Question 2

Griffith’s Experiments

Answer 2

Streptococcus pneumoniae, only pathogenic when it has a capsule. S-Strain has capsule R-strain doesn’t. Showed the killed S-strain could pass capsule trait to R-strain and kill mice.

Question 3

Avery, MacLeod, and McCarty’s Experiment

Answer 3

Follow up on Griffith’s work. Used enzymes to degrade proteins, DNA and RNA in various samples. Showed that DNA was responsible for transformation.

Question 4

Hershey and Chase Experiments

Answer 4

Confirmed DNA as genetic material. Concluded that only phage DNA enters the cell

Question 5

Hershey and Chase used what kind of infection agent

Answer 5

Bacteriophages - Viruses that can infect bacteria and have a standard DNA genome

Question 6

Hershey and Chase Experiments used what to tag DNA

Answer 6

Used radioactive sulfur to tag proteins. Because protein has sulfur and DNA never does. If sulfur is there protein is there.

Used Radioactive phosphorus to tag DNA. All DNA has phosphorus.

Question 7

Nucleotide Monomers consist of

Answer 7

Nitrogenous base, deoxyribose, Pentose sugar (5-Carbon Sugar) 1-3 phosphate groups (Energy).

Question 8

Nitrogenous Bases and their defining structure

Answer 8

Pyrimidines - Single 6-carbon ring structure. Purines - Double Ring Structure

Question 9

Pyrimidines in DNA

Answer 9

Cytosine, Thymine (Unique to DNA). Single 6-Carbon Ring Structure

Question 10

Purines in DNA

Answer 10

Adenine, Guanine. Double Ring Structure

Question 11

Why does DNA polymerization occur in the 5’ -> 3’ direction

Answer 11

Because 5’ carbon brings in the phosphate groups which supplies the energy for DNA polymerization.

Question 12

Chargaff’s Rule

Answer 12

Chargaff found that the amount of adenine in DNA sample matched Thymine and the amount of cytosine matched guanine

Question 13

Rosalind Franklin’s Work

Answer 13

Used X-ray diffraction to see DNA and show that it was a double helix

Question 14

Watson and Crick’s work

Answer 14

Confirmed the double Helix nature of DNA. Stole Rosalind’s work. Showed DNA was two antiparallel strands

Question 15

How are DNA strands held togethere?

Answer 15

DNA strands are held together by hydrogen bonding. Two hydrogen bonds between A - T and three bonds between G - C

Question 16

DNA Denaturing

Answer 16

DNA can be denatured with heat into ssDNA (Single Stranded)

Question 17

DNA Reannealing

Answer 17

Under the right conditions ssDNA can reanneal or come back together into a double stranded DNA

Question 18

Vertical Gene Transfer

Answer 18

Passing of DNA from parent to offspring

Question 19

Components of RNA nucleotides

Answer 19

Pentose Sugar - Ribose. 1-3 Phosphate Groups - Energy. Typically, single stranded but can fold on itself by complementary base pairing.

Question 20

Nitrogenous bases in RNA

Answer 20

Uracil - No thymine in RNA. Cytosine. Adenine. Guanine.

Question 21

mRNA in protein synthesis

Answer 21

Produced by transcription. Temp copy of a gene. Serves as intermediary between DNA and protein used by ribosomes.

Question 22

tRNA in protein synthesis

Answer 22

Attached to an amino acid. Brings amino acid for translation. carries the correct amino acid to the site of protein synthesis in the ribosome

Question 23

rRNA in protein synthesis

Answer 23

Component of ribosome structure along with protein. Essential for translation. Ensure the proper alignment of mRNA, tRNA, and ribosome; catalyzes peptide bond formation

Question 24

Genotype

Answer 24

collection of all genes within the genome

Question 25

Phenotype

Answer 25

observable characteristics.

Question 26

Prokaryotic Chromosomes Characteristics

Answer 26

Typically circular and haploid (not paired). Multiple supercoiled regions which stabilize by DNA gyrase (is a Topoisomerases). Histone-like binding proteins. Proteins bind to origin of replication

Question 27

Eukaryotic Chromosomes Characteristics

Answer 27

Typically, linear and diploid (paired). DNA must be packaged to fit inside the cell.

Question 28

Supercoiling

Answer 28

Highly twisted DNA to fit inside nucleus.

Question 29

Topoisomerases

Answer 29

help stabilize supercoil and prevent overwinding of DNA during processes like DNA replication.

Question 30

Histones

Answer 30

DNA wrapping and attachment to scaffolding proteins

Question 31

Chromatin

Answer 31

combination of DNA and attached proteins.

Question 32

Non-Coding DNA

Answer 32

Does not code for a protein or stable RNA products. Commonly found at start of coding region and between genes

Question 33

Non-Coding DNA in Prokaryotes

Answer 33

Much less common in prokaryotes (only around 12% of genome) vs around 98% in eukaryotes

Question 34

Non-Coding DNA is not “junk” DNA because

Answer 34

Many contribute to regulation of transcription or translation by coding for small noncoding RNA molecules, DNA packaging, and chromosomal stability.

Question 35

Extrachromosomal DNA examples

Answer 35

Mitochondria and chloroplast - eukaryotes

Question 36

Plasmids significance in Prokaryotes

Answer 36

Contains genes not essential for growth. Nice to have, but don’t need them to survive. Can pass on traits like antimicrobial resistance.