Cell Structure

Question 1

The Cell Theory

Answer 1

1. All organisms consist of one or more cells
2. The cell is the basic unit of structure for all organisms
3. All cells arise only from preexisting cells

Question 2

Where did the first cells come from?

Answer 2

Abiotic (non-living) synthesis of simple organic compounds

Question 3

What were the earliest cells?

Answer 3

Liposomes and RNA (possibly)

Question 4

Plasma Membrane

Answer 4

Surrounds every cell and ensures that cell contents are retained

Question 5

What is the plasma membrane composed of?

Answer 5

Lipids (including phospholipids) and membrane proteins that are organized into a bi-layer

Question 6

Glycoproteins

Answer 6

Membrane proteins with polysaccharides attached to them

Question 7

Extracellular Matrix

Answer 7

• Found in animal cells

Provides structural support and regulates cell migration, cell recognition, and cell adhesion

Question 8

What is the extracellular matrix composed of?

Answer 8

Collagen (protein) & proteoglycans

Question 9

Cytoskeleton

Answer 9

Interconnected protein structures within the cytoplasm

- Gives the cell its shape & internal organization

Question 10

Nucleus

Answer 10

Contains DNA organized into chromosomes

Question 11

What is the nuclear envelope composed of?

Answer 11

Two lipid bi-layers

Question 12

Nuclear pores

Answer 12

Protein channels in the nuclear envelope that allow transport between the nucleus and cytoplasm

Question 13

Mitochondria

Answer 13

Organelle involved in energy production for cells

- Site of aerobic respiration

Question 14

Chloroplast

Answer 14

Convert solar energy to glucose

Question 15

Ribosomes

Answer 15

Used by all living cells to translate mRNA and synthesize proteins
- Not considered a true organelle

Question 16

Viruses

Answer 16

• Not cells
• Composed primarily of nucleic acids & proteins
• Invade and infect cells