1.17-18

Question 1

What can epigenetic changes lead to between identical siblings and clones?

Answer 1

Differences

Epigenetic changes can affect gene expression without altering the DNA sequence.

Question 2

What diseases can epigenetic changes cause?

Answer 2

Human diseases

This includes conditions like cancer and autoimmune diseases.

Question 3

How can environmental factors influence epigenetic changes?

Answer 3

Through diet and drug use affecting DNA methylation

Factors like malnutrition and drug use during pregnancy are particularly impactful.

Question 4

What role do epigenetic factors play in autoimmune diseases?

Answer 4

Evidence suggests involvement in their development

This indicates a connection between epigenetics and immune system disorders.

Question 5

What is cancer primarily caused by?

Answer 5

Unregulated cell division

This leads to the formation of tumors.

Question 6

What are proto-oncogenes and tumor suppressing genes?

Answer 6

Important genes that regulate cell division

They are affected by DNA methylation.

Question 7

What are changes in the DNA sequence called?

Answer 7

Mutations

Mutations can affect the nucleotide base sequence of DNA.

Question 8

What can a change in a single nucleotide base affect?

Answer 8

The mRNA codon sequence and the primary structure of the protein

This can lead to different protein functions.

Question 9

What can mutations in genes and chromosomes result from?

Answer 9

Errors in DNA replication or cell division, or environmental damage

Physical or chemical factors can also contribute.

Question 10

What are the types of mutations?

Answer 10

• Deletions
• Insertions
• Substitution
• Inversion

Each type can lead to various effects on protein function.

Question 11

What is a missense mutation?

Answer 11

A mutation that results in a different amino acid

This can alter protein function.

Question 12

What is a same-sense mutation?

Answer 12

A mutation that causes no change due to multiple codes for the amino acid

This is often referred to as a silent mutation.

Question 13

What is a non-sense mutation?

Answer 13

A mutation that codes for a stop codon and leads to chain termination

This has a significant effect on protein synthesis.

Question 14

What is a frameshift mutation?

Answer 14

A mutation caused by insertions or deletions that cause big changes

This disrupts the reading frame of the genetic code.