Genetics and Cellular Function

Question 1

DNA Function

Answer 1

Serves as a code for protein synthesis. (blueprints)

Question 2

Gene

Answer 2

Sequence of DNA nucleotides that codes for one polypeptide

Question 3

Genome

Answer 3

All the genes of one person.

Question 4

How many genes do humans have?

Answer 4

35,000

Question 5

RNA structure and function

Answer 5

Much smaller than DNA. Essential function is to interpret DNA code and to direct protein synthesis in the cytoplasm

Question 6

How are our hormones released?

Answer 6

The growth hormone hits DNA and it sends RNA out to tell other enzymes to make the protein.

Question 7

Errors and Mutations

Answer 7

Changes in DNA structure due to replication errors or environmental factors. Cancer has mutant cells that stay alive and reproduce at dramatic rates.

Question 8

When do cells divide? 4

Answer 8

-Have enough cytoplasm for 2 daughter cells
DNA replicated
-Adequate supply of nutrients
-Growth factor stimulation
-Open space in tissue due to neighboring cell death

Question 9

When do cells stop dividing? 2

Answer 9

• Loss of growth factors or nutrients

- Contact inhibition

Question 10

Heredity

Answer 10

Transmission of genetic characteristics from parent to offspring

Question 11

How many chromosomes do we get from our parents?

Answer 11

23 from mom and 23 from dad

Question 12

How many chromosomes do sperms and eggs have?

Answer 12

23

Question 13

Tumors

Answer 13

(neoplasms)Abnormal growth, when cells multiply faster than they die. Oncology is the study of tumors

Question 14

Benign (tumor)

Answer 14

Will not cause any effect, except for putting pressure on other organs

Question 15

Malignant

Answer 15

Unencapsulated, fast growing, metastatic (causes 90% of cancer deaths) They can Displaces normal tissue, organ function deteriorates. Block vital passageways. Diverts nutrients from healthy tissues

Question 16

Carcinogens

Answer 16

A cause of cancer. Estimates of 60 - 70% of cancers from environmental agents. It can be chemical, radiation, or viruses.

Question 17

Mutagens

Answer 17

Trigger gene mutations. The cell may die, be destroyed by immune system or produce a tumor

Question 18

Defenses against mutagens 4

Answer 18

Scavenger cells-remove them before they cause genetic damage
Peroxisomes-neutralize nitrites, free radicals and oxidizing agents
Nuclear enzymes-repair DNA
Tumor necrosis factor (TNF) from macrophages and certain WBCs destroys tumors (white bloods cells attack the tumor

Question 19

Oncogenes

Answer 19

Genes from parents that make you more likely to get cancer

Question 20

Tumor suppressor genes

Answer 20

Genes that make you less likely to have cancer. If damaged you are more likely to trigger cancer.