Ch 4 Prokaryotic Cells & Microorganisms

Question 1

What are some characteristics that all living things have on a cellular level?

Answer 1

• Basic Shape
• Internal content
• DNA Chromosomes
• Ribosomes
• Metabolic capabilities

Question 2

What are two types of cells?

Answer 2

Eukaryotic & Prokaryotic

Question 3

Eukaryotic

Answer 3

Cells that have a nucleus & membrane-bound organelles
Ex: animals, plants, fungi, & protists

Question 4

Prokaryotic

Answer 4

Cells that lacks nucleus and membrane-bound organelles
Ex: bacteria & archaea

Question 5

Characteristics of Life

Answer 5

1. Reproduction & Heredity
2. Growth & Development
3. Metabolism
4. Movement
5. Cell support, protection, & storage
6. Transport of nutrients & waste

Question 6

Appendages Found in Prokaryotes

Answer 6

Flagella, Pili, and Axial Filaments

Question 7

Define Flagellar Response & its purpose

Answer 7

1. Def: Guides bacteria in a direction in response to external stimuli
2. Stimuli signal sets the flagella into motion
   - Counterclockwise: smooth linear direction
   - Clockwise: tumbles

Question 8

What is Fimbriae and its function?

Answer 8

• Fine hairlike bristles emerging from the surface of the cell
• Function: sticks onto cells and surfaces

Question 9

What is Pili? Where is it found, and what is its purpose?

Answer 9

It is a rigid tubular structure made of pilin protein, found in gram-negative cells.
Function: joins bacterial cells for partial DNA transfer called conjugation

Question 10

External Structure of Prokaryotes (Outer to inner layer)

Answer 10

The external function is known as Cell Envelope. It consists of…
1. Glycocalyx (surface coating)
2. Cell membrane
3. Cell wall

Question 11

Functions of Glycocalyx

Answer 11

• Protecting cells from dehydration & nutrient loss
• Prevents killing by white blood cells
• Attachment: formation of biofilms

Question 12

What is inside bacterial cells (prokaryotes)?

Answer 12

• Cytoplasm
• DNA chromosomes
• Ribosomes
• Plasmids

Question 13

Cytoplasm

Answer 13

Dense gelatinous solution of sugars, amino acids, and salts

Serves as a solvent for materials used in all cell functions

Question 14

Chromosome

Answer 14

Threadlike structure made up of nucleic acids that contains all the genetic information

Question 15

Plasmids

Answer 15

Free small circular, double-stranded DNA

Not essential to bacterial growth and metabolism

Used in genetic engineering - readily manipulated and transferred from cell to cell

Question 16

Ribosomes

Answer 16

Made up of RNA & Protein

Translates genetic code to amino acids to create protein polymers

Site of protein synthesis

Found in all cells

Question 17

Bacterial Internal Structure

Answer 17

1. Inclusions and granules
2. Cytoskeleton
3. Endospores
4. Sporulation
5. Germination

Question 18

Inclusions and granules

Answer 18

Intracellular storage bodies

Vary in size, number, and content

Bacterial cells can use them when environmental sources are depleted

Question 19

Cytoskeleton

Answer 19

An internal network of protein polymers that is closely associated with the cell wall

Question 20

Endospores

Answer 20

Inert, resting, cells produced by some G+ genera: Clostridium, Bacillus, and Sporosarcina

Question 21

Sporulation

Answer 21

It is the formation of endospores:

• most rigid compared to all life forms
• withstands extremes in heat, drying, freezing, radiation, and chemicals
• no reproduction

Question 22

Germination

Answer 22

Returns to vegetative growth