Cells

Question 1

What is the cell theory?

Answer 1

1. All living things are made up of cells. Cells are the fundamental unit of life.
2. Every cell comes from pre-existing cells
   Ex. Mitosis and meiosis

Question 2

What are the two types of cells?

Answer 2

1. Prokaryotic (simple)
   -lacks most organelles
   -have flagella if motile (thing that allows it to move)
   -cell wall
   -lacks nuclear envelope
   -single circular DNA chromosome in nucleoid region
   Ex. Bacterium
2. Eukaryotic (complex)
   -has most organelles
   -linear chromosomes
   -nuclear envelope

Question 3

What is resolving power

Answer 3

The ability to define two points as separate

Question 4

What is the relationship between wavelength and resolving power?

Answer 4

Inverse relationship/indirect proportional

Resolving power is indirectly proportional to the wavelength

Question 5

Explain why electron microscopes have a greater resolution than light microscopes

Answer 5

Electron microscopes have the ability to distinguish two very small points through electrons. They are used to view preserved tissue and internal details of cells, therefore needing higher resolving power. Electrons have smaller wavelengths in comparison to light wavelengths and according to the relationship between resolving power and wavelength (indirectly proportional), smaller wavelengths produce higher resolving power.

Question 6

What is the purpose of the Endomembrane system?

Answer 6

To produce and secrete proteins

Question 7

What is the process of creating a protein?

Answer 7

Endomembrane system

1. Make a copy of gene segment called mRNA, contains specific instructions to create protein (planning site)
2. Moves to RER through nuclear pore to prepare for construction
3. Ribosomes read instructions in mRNA to construct a specific pattern of amino acids (20 kinds) and start protein synthesis (ER = construction site)
4. Protein is then transported to the Golgi apparatus in a transport vesicle (budding)
5. Golgi apparatus refines, modifies, activates the protein for use
6. Protein is transported to cell membrane in secretory vesicle
7. Secretory vesicle migrates to the cell wall and releases the product (exocytosis)

Question 8

What are proteins?

Answer 8

A specific sequence of amino acids for cell use.

Question 9

What are the different types of proteins?

Answer 9

1. Structural protein (muscle, connective tissue, tendons, ligaments)
2. Enzymes (pepsin in stomach)
3. Neurotransmitters
4. Protein based hormones (insulin)

Question 10

What is the purpose of smooth endoplasmic reticulum?

Answer 10

1. Detoxification
   -breaks down toxins and harmful compounds
   Ex. Liver cells have a lot of SER
2. Lipid (fat)/ Steroid synthesis
   Ex. Gatorade creates steroid hormones thus they have large amounts of SER, also gonadal cells

Question 11

What are the functions of lysosomes?

Answer 11

1. Cellular Digestion
   - lysosomes use hydrolytic enzymes and fuses with vacuoles to break down macromolecules
2. Autolysis (self-destruction)
   - cell produces a large numbers of lysosomes in order to break itself down as it can’t function properly anymore
   - digests organelles

Question 12

What is the function of mitochondria?

Answer 12

'’Tis the powerhouse of the cell me friend.

-ATP molecule fuels chemical reactions in the body, which is produced in the mitochondria (energy currency of the cell)

Question 13

What is cellular respiration/glycosis?

Answer 13

Glucose (sugar) + O2 => ATP + CO2 + H2O

Question 14

How is the mitochondria believed to be born?

Answer 14

Endosymbiosis

-the theory that mitochondria originated from a symbiotic relationship between a single cellular organism and a bacteria

Question 15

What is analogous to the mitochondria in the plant cell?

Answer 15

Photosynthesis

-energy from the sun plus water plus CO2 produces glucose and O2

Question 16

Cytoplasm

Answer 16

• fluid within the cell
• suspends organelles
• dissolving medium, transports substances to different places

Question 17

What are microfilaments?

Answer 17

They provide strength and cell mobility

Ex. Propulsion system (sperm moving, microfilaments expand)

Question 18

What is the cell membrane also known as?

Answer 18

Phospholipid bilayer, fluid mosaic model, plasma membrane

Question 19

What is the phospholipid bilayer?

Answer 19

Cell membrane

A double layer of phospholipids

Question 20

What is the fluid mosaic model?

Answer 20

Cell membrane

• transmembrane proteins within bilayer gives mosaic latter. Ex. Channels, receptors
• proteins embedded in phospholipids
• in constant motion

Question 21

What is the plasma membrane?

Answer 21

Cell membrane
-provide support and protection for the cell
-has selectively permeable membrane
=> barrier to regulate substance and out of the cell
=> control passage/time

Question 22

What is the nucleus?

Answer 22

Structure that contains DNA

Question 23

What is the nuclear envelope?

Answer 23

It has a membrane structure

• the nuclear pores regulates movement in/out of nucleus
• nucleolus makes RNA for new ribosome synthesis

Question 24

What purpose does DNA serve?

Answer 24

-contains genes for personal traits
-replicates, passes info on to next generation of cells or individuals
Stores codes for protein synthesis
Random mutation to allow variation within species in an environmental shift

Question 25

What are the similarities and difference between cromatin and chromosomes?

Answer 25

They are both composed of DNA. Cromatin is present during interphase Disperse and diffuse DNA strands Chromosomes are present only during replication They are condensed DNA strands during replication.