Cell Structures: Background Info (Part 1)

Question 1

What is DNA?

Answer 1

Carries all the genetic information of the organism, coiled into long molecules, found in the nucleus of the cell.
- Constructed of four bases
- Adenine with Thymine, Cytosine with Guanine (apple in tree, car in garage)
- These millions of pairs of bases make up each organism’s unique genetic code

Question 2

What are genes?

Answer 2

Sections of DNA that direct cell function. “Patterns” that code traits, including amino acids (protein), testosterone, everything.
- Changes in genes can cause improper cell function. Ex: Sickle cell anemia

Gene Sequencing: Determining the order of all of a gene’s bases
Gene Therapy: The gene is corrected to cure the disorder

Question 3

Why are cancers dangerous?

Answer 3

They don’t have apoptosis (programmed self-suicide in case things go wrong); don’t stop

Most cancers are caused by gene damage, which causes mutations in DNA. Cancerous cells divide indefinitely and form layers upon layers to create a tumour.

Question 4

What is mutation?

Answer 4

Change in the base sequence of a gene which causes damage

Question 5

What is a virus?

Answer 5

Non-cellular structure is made of a piece of genetic material enclosed in a protein coat.
- To reproduce, a virus must infect another cell and use its host cell’s organelles (cell parts)

Question 6

What is a prion?

Answer 6

A protein that can convert into a harmful particle which can reproduce in living tissue
- Causes BSE (bovine spongiform encephalopathy) or mad cow’s disease

Question 7

What is cell culture?

Answer 7

Isolated cells are given nutrients and their growth and division are studied. Ex: Petri-dish

Question 8

What is a cell line?

Answer 8

The generations of cells produced from a culture; can be grown indefinitely, as long as we keep providing space.

Ex: HeLa cells, taken from cancer patient Henrietta Lacks in 1951 without family knowledge. Used in research to test the first polio vaccine and very easy to grow in lab settings.

Question 9

What are stem cells?

Answer 9

“Blank slate” cells that divide to produce all other types of specialized cells
- Mature into specialized cells which can then only produce to form more of their kind. Ex: growth into liver cells can only then be liver cells.
- Scientists hope to grow tissues and organs for transplants and to cure diseases using stem cells (ex: Spinal cord injuries, Alzheimer’s)
(Virchow was the first to link leukemia to malfunctioning cells)

Found in:
1. week old embryos (fetuses)
2. adult stem cells: bone marrow
3. unused eggs from in-virto fertilization
4. umbilical cord blood
5. genetically engineered from other human stem cells
6. skin cells