Microbial Cell Structure and Function

Question 1

It deals with the size, shape and arrangement of a living organism

Answer 1

Morphology

Question 2

The study of the size and shape of the cell

Answer 2

Cell Morphology

Question 3

What is the approximate size of bacteria?

Answer 3

3 micrometer

Question 4

What is the size of cocci?

Answer 4

ranging from 0.5 to 3 micrometer

Question 5

What is the size of bacilli?

Answer 5

ranging from 0.15 to 2 micrometer (width) to 0.5 to 20 micrometer (length)

Question 6

What are the bacterial shapes? define each one.

Answer 6

Cocci - spherical and ovoid
Bacilli - cylindrical
Spiral - curve or loose spiral

Question 7

What are the Bacterial arrangements?

Answer 7

Singly - single
Strepto - in chain
Staphylo - in cluster
Diplo - in pairs
Sarcinae - three dimensional cubes

Spirochetes - tightly coiled

Question 8

What are the three major functions of the cytoplasmic Membrane in prokaryotic cells?

Answer 8

1. Barrier preventing the passive leakage of solutes into or out of the cell.
2. anchors several proteins that catalyze a suite of key cell functions.
3. plays a major role in energy conservation and consumption.

Question 9

What is the mode of movement of bacteria or microorganisms to transfer any disease?

Answer 9

Vector

Question 10

What do hydrophobic and hydrophilic mean?

Answer 10

Water-repelling and water-attracting

Question 11

Strengthened by sterol-like molecules that is present in bacteria

Answer 11

Hopanoids

Question 12

This strengthens the membranes of eukaryotic cells where there is an absence of cell wall.

Answer 12

Sterols

Question 13

Take note of this and memorize!

Answer 13

the cytoplasmic membrane of Archaea is structurally similar to those of bacteria and Eukarya, but chemistry is somewhat different.

Question 14

The layer outside the cytoplasmic membrane; gives shape and rigidity to the cell.
confers structural strength on the cell in order to keep it from bursting due to osmotic pressure

Answer 14

Cell wall

Question 15

Two major group of Cell Wall

Answer 15

Gram-positive
Gram-negative

Question 16

This cell wall is thicker and has single type of molecule

Answer 16

Gram-positive

Question 17

This cell wall consist of two layers

Answer 17

Gram-negative

Question 18

List the three osmotic pressure and give their definitions

Answer 18

1. hypertonic - cell shrinks, H2O goes outward
2. Isotonic - balance, H2O goes in and out
3. hypotonic - cell bursts, H2O goes inward

Question 19

weakens the peptidoglycan and causes cell lysis.
acts as a major line of defence against bacteria.
destroys pre-existing peptidoglycan

Answer 19

Lysozyme

Question 20

Made up of rigid polysaccharides.
not present in archaea and eukarya.

Answer 20

Peptidoglycan

Question 21

Space located between the outer surface of the cytoplasmic membrane and the inner surface of the outer membrane spans about 15nm

Answer 21

Periplasm

Question 22

Channels for the entrance and exit of solutes

Answer 22

Porins

Question 23

Forms water-filled channels through which virtually any very small hydrophilic substance can pass

Answer 23

Non-specific porins

Question 24

Contain a binding site for one or a group of structurally related substances

Answer 24

Specific porins

Question 25

cell walls of a certain methane-producing Archaea

Answer 25

Methanogens

Question 26

is a Latin word for wall and was an old term for peptidoglycan

Answer 26

Murein