Prokaryote + Eukaryote

Question 1

What are bacterial cells measured in?

Answer 1

• Microns (µm)

- Nanometers (nm)

Question 2

Bacterial cell Morphology: shapes and patterns. What shapes can bacteria have? 6 (S.S.R - S.T.F)

Answer 2

• Rod shaped ( Bacilli)
• Spherical shaped ( Cocci)/coccus
• Spiral shaped (Spirilla)/ spirillum
• Star Shaped
• Triangular shaped
• Flat

Question 3

Slide 7

Answer 3

look at it.

Question 4

What is Gram- Positive bacteria + give and example.

Answer 4

• Thick cell wall (up to 80nm thick)
• Peptidoglycan is highly cross linked

e.g. S. aureus

Question 5

What is Gram- Negative bacteria + give and example.

Answer 5

• Thin cell wall ( 10nm or less)
• Peptidoglycan not fully cross-linked
• Has an outer membrane.

Question 6

What is Gram-staining?

Answer 6

• A differential stain that utilizes 2 dyes, Crystal violet and Safranin, to differentiate between the two categories.

Question 7

Describe the bacterial cell wall?

Answer 7

• Rigid structure (gives cell its characteristic shape).
• Stops inward diffusion of H2O w/out it the cell membrane would swell + burst.

Read - The antibiotic Penicillin interferes with the ability of cells to synthesis normal cell walls making subsequent cell susceptible to cell lysis. The is the mechanism of action of the ‘wonder drug’ Penicillin and related compounds….the so called magic bullet because human cells lack cell walls.

Question 8

Where are bacterial spores formed?

Answer 8

• From within the cell.

Resistant to heat, drying, radiation and a variety of chemical compounds including alcohol.

Question 9

look at slide 13

Answer 9

learn

Question 10

Draw and label a plant and animal cell.

Answer 10

draw them (slide 16+17)

Question 11

What is the function of the cell wall? (S.P.F)

Answer 11

• Protects + supports the cell.
• Is flexible + extensible allows for increase in cell size.
• Is strong but leaky (cardboard like) allows water + chemicals pass through.

Read- Once the cell reaches its final size and shape, the rigid secondary cell wall forms by deposition of additional cellulose and lignin on the inner surface of the primary cell wall

Question 12

What a plant and fungal cells made of respectively?

Answer 12

• Plant: Cellulose (carb)

- Fungal: Pectin (carb)

Question 13

What are bacterial cell walls composed of?

Answer 13

• Peptidoglycans (glycoproteins).

Question 14

What is the function of a cell membrane/plasma membrane?

Answer 14

• By surrounding the cell this ensures that the cells contents are retained.

Question 15

What is the cell/plasma membrane composed of?

Answer 15

• lipids (in fatty acids) + Phospholipids. (PHOSPHOLIPD BILAYER)
• Membrane Proteins

Question 16

Read

Answer 16

▪ The membrane is not strong, but is
water-tight.
▪ Communicates with other cells
▪ Certain gate-keeping proteins in the cell membrane will let things in and out.

Question 17

What is the cytoplasm?

Answer 17

• Semi fluid CYTOSOL in which organelles, cytoskeletal fibers are suspended

molecules move through the cytoplasm by diffusion

Question 18

What are Microfilaments?

Answer 18

• Act as contractile elements that

generate tension.

Question 19

What are Intermediate Filaments?

Answer 19

• Are elastic + can w/stand tensile forces.

Question 20

What is the Cytoskeleton made of?

Answer 20

• Microtubules, intermediate filaments & microfilaments made of proteins.

Question 21

What is he function of the Cytoskeleton?

Answer 21

• The cytoskeleton gives a cell its shape and allows the cell to organize its internal components and to move.
• Like a conveyor belt bc it acts framework for positioning and moving organelles and macromolecules within the cell

Question 22

What are Microtubules?

Answer 22

• They resist bending when a cell is compressed.

Question 23

What is The 
Extracellular Matrix (ECM) made from?

Answer 23

• Mix of proteins + polysaccharides secreted by the cell.

Question 24

Read The ECM

Answer 24

• Located Outside plasma membrane. Connected to cytoskeletal fibres and transmembrane proteins.
• • In animals, ECM’s are enriched in proteins such as collagens (the main structural protein in
  connective tissue), elastin, fibronectin, laminins and glycoproteins.
  • Bone is mostly made of EM (fibrous collagen, hardened by mineral deposits).

Question 25

What is the function of the Extracellular Matrix?

Answer 25

• Support + Anchorage (by filling the spaces between cells + binding cells + tissues together)

Question 26

Organelles

Answer 26

▪ nucleus
▪ endoplasmic reticulum, 
▪ Golgi complex, 
▪ mitochondria, 
▪ chloroplasts, 
▪ lysosomes, 
▪ peroxisomes, various types of vacuoles and vesicles

• membrane-bounded compartments that are
  specialized for specific functions.
• Each organelle contains the materials and molecular machinery needed to carry out the functions for which the structure is specialized.
• Each organelle is surrounded by a membrane that makes it separate from the cytosol.

Question 27

What is the Nucleus?

Answer 27

• contains the genetic info which tells the cell machinery which proteins to make and how they are assembled.

Question 28

What is the genetic info coded in?

Answer 28

• DNA (deoxyribonucleic acid
• Which is packaged into chromosomes.

Separates DNA from substances in cytoplasm

Question 29

What is the nucleus composed of? (N-l,r,p- N.N.C)

Answer 29

• Nuclear Envelope ( Lipid Bilayer, Ribosomes, Pores).
• Nucleolus ( where ribosomes subunits are made).
• Nucleoplasm (Fluid interior of the nucleus).
• Chromosomes (DNA molecules folded + twisted into condensed structures).