Test 7 - Lecture 3

Question 1

According to the video What Happens When Your DNA Is Damaged, what can be a rad results of a lot of damage done to your DNA?

Answer 1

Many serious issues, such as cancer

Question 2

According to the video What Happens When Your DNA Is Damaged, one common error is base mismatches. What takes place during this error?

Answer 2

DNA polymerase brings together a pair incorrectly (adenine going with guanine instead of thymine)

Question 3

According to the video What Happens When Your DNA Is Damaged, one common error is base mismatches. How does mismatch repair occur to fix these problems?

Answer 3

The enzyme cuts off a few nucleotides and replaces it with correct one, and a second set of proteins check right after to make sure there are no mismatches

Question 4

According to the video What Happens When Your DNA Is Damaged, how can DNA get damaged after DNA replication?

Answer 4

Certain natural molecules can cause chemical damage to nucleotides, such as hydrogen peroxide

Question 5

According to the video What Happens When Your DNA Is Damaged, if only one nucleotide is damaged after DNA replication, what type of repair can take place to fix the problem and how it is done?

Answer 5

Excision repair - One enzyme removes the damaged base and other enzymes come in to trim around the site and replace the nucleotides

Question 6

According to the video What Happens When Your DNA Is Damaged, how can UV light damage DNA?

Answer 6

It can cause two adjacent nucleotides to stick together which distorts the DNA’s double helix

Question 7

According to the video What Happens When Your DNA Is Damaged, how does nucleotide excision repair fix damaged DNA?

Answer 7

Proteins remove a long strand of 24+ nucleotides and replaces them with new ones

Question 8

According to the video What Happens When Your DNA Is Damaged, why are double strand breaks the most dangerous?

Answer 8

It can cause cell death, or the severing of strands of the DNA backbone

Question 9

According to the video What Happens When Your DNA Is Damaged, what are the names of the two types of repair that can fix double-strand breaks in the DNA backbone?

Answer 9

Homologous recombination, non-homologous end joining

Question 10

According to the video What Happens When Your DNA Is Damaged, there are two types of repair that can fix double-strand breaks in the DNA backbone. How does each type fix these kinds of breaks?

Answer 10

Homologous recombination: Uses undamaged section of similar DNA as a template, enzymes interlace damaged X undamaged strands to have them exchange sequences of nucleotides and fill in the missing gaps

Non-homologous end joining: Series of proteins trim off a few nucleotides, then fuses the broken ends back together

Question 11

Our bodies have many different specific DNA repairs systems. Which statement describes the UVR photorepair system?

Answer 11

The system that repairs damage caused by UV light, and corrects the thymine dimers that form

Question 12

Our bodies have many different specific DNA repairs systems. Which statement describes the Aprymidinic (AP) site repair?

Answer 12

A repair system which repairs any instances where your cell is present in DNA by mistake

Question 13

Which statement is true regarding excision repairs? (know what they are, what they can fix, and how they are used)

Answer 13

Repairs the DNA when there are replication errors and chemical damage

Question 14

__________________ repair is the only repair system able to handle double-strand breaks in DNA and can be found within eukaryotes. Fill in the blank.

Answer 14

Post-replication repair

Question 15

Recombinational repair can occur within which phases of meiosis or mitosis within eukaryotes?

Answer 15

Prophase

Question 16

What is the main function of a ribosome?

Answer 16

Create ribosomes

Question 17

Ribosomes are composed of two subunits, what happens when they are joined together and what occurs when they are separated?

Answer 17

Together: The “factory” works and create polypeptides/proteins
Separated: You simply cannot make proteins

Question 18

Protein synthesis takes place on three different sties called the _________, ___________, and ___________ site of a ribosome. Fill in the blanks.

Answer 18

E, P, A

Question 19

What is the main function of (a) rRNA, (b) tRNA, or (c) mRNA?

Answer 19

A) Polypeptide making factories made up of two subunits
B) Responsible for transporting amino acids to ribosomes to create proteins
C) A copy of your DNA that will tell you the instructions on how to create the proteins

Question 20

Human have approximately how many tRNAs within their cells?

Answer 20

45

Question 21

Which statement briefly describes how mRNA, rRNA, and tRNA work together within your cells? (we discussed it on chapter fifteen slide five)

Answer 21

mRNA is inserted into the rRNA ribosomes, tRNA brings amino acids to build the proteins

Question 22

Which statement describes the central dogma of gene expression (i.e. what is gene expression)?

Answer 22

Theory that genetic information flows in one direction: DNA –> RNA –> Protein, or RNA directly to the protein

Question 23

Which sentence briefly describes the overview of what occurs and what is produced during the process of transcription? (know the information we discussed on chapter fifteen slide eight)

Answer 23

Produce an mRNA strand from DNA, make one strand copy of it and the end product is mRNA

Question 24

Which sentence briefly describes the overview of what occurs and what is produced during the process of translation? (know the information we discussed on chapter fifteen slide nine)

Answer 24

Inserting mRNA strand which attaches to the ribosome in the cytoplasm and brings tRNAs with amino acids and drops them off inside the ribosome and creating proteins

Question 25

Each block of three nucleotides, called a _______________, corresponds to an amino acid in the encoded protein called a ______________. Fill in the blanks.

Answer 25

Codon, codon triplet codes

Question 26

Is the genetic code similar in all organisms? Know the answer either yes or no and know the example discussed in lecture.

Answer 26

Yes, AGA specifies the amino acid, arginine, in all organisms that have been studied

Question 27

Is the mitochondrial code similar in all organisms? Know the answer either yes or no and know the example discussed in lecture.

Answer 27

No, the mitochondria and chloroplasts read the portion of the code associated with the stop signals, differently from each other