Chapter 3- Cell Structure and Function

Question 1

Characteristics common to all living things:

Answer 1

Growth
Reproduction
Responsiveness
Metabolism

Question 2

Are viruses a living organism and why?

Answer 2

No, they aren’t cells and don’t satisfy any of the characteristics that are common to all living things

Question 3

Brief differences between prokaryote and eukaryote cells

Answer 3

Prokaryote: no nucleus, lacks membrane-bound organelles, and uses binary fission

Eukaryote: nucleus, has membrane-bound organelles, and uses mitosis

Question 4

Glycocalyx
–composed of..
-function
-where is it found
-describe it

Answer 4

Composed of polysaccharide, polypeptide, or both

Prevents desiccation (drying out), evade phagocytosis, attachment

Found attached to the cell wall (it’s made up of a gelatinous sticky substance that forms the outermost layer of the cell exterior to the cell wall)

Question 5

Glycocalyx:

If the sticky substance is ____ and ____ attached to the bacterial cell wall, the glycocalyx is described as a _____
v.s
If the sticky substance is ____ and ____ attached to the bacterial cell wall, the glycocalyx is described as a _____

Answer 5

Organized and firmly attached = capsule

Unorganized and loosely attached = slime layer

Question 6

The cell wall gives bacterial cells a specific ___ and functions to ______ _____ from ______ ____. It also assists some cells in __________________ and contributes to resisting ______ drugs.

Answer 6

shape

protect destruction from osmotic forces

it assists some cells in attaching to other cells and contributes to resisting antimicrobial drugs

Question 7

Mycoplasmas

Answer 7

Do not fit in either gram-positive or gram-negative bacteria

Lacks cell walls and has undefined shapes

Question 8

The cell wall of a gram-positive bacteria forms a ____, rigid structure. It has many layers of ________, which refers to a chemical molecule that is part ___ and part _______.

Answer 8

thick

peptidoglycan molecules

protein
polysaccharide

Question 9

Gram-positive bacteria:
The ______ part of peptidoglycan consists of long chains of repeating alternating molecules called ___ and ____. The layers are held together by ______ ________.

Answer 9

polysaccharide

NAG and NAM

tetrapeptide crossbridges

Question 10

Gram-positive bacteria:

The peptidoglycan layer also contains teichoic acid and (1) _____ _____. What does (1)______ ___ do?

Answer 10

Lipoteichoic acid

It attaches the cell wall to the cell membrane

Question 11

The cell walls of a gram-negative bacteria consist of a ____ ________ ___ surrounded by an outer membrane. Similar to gram-positive bacteria, they have alternating ___ and ____ structures, but they don’t have ______ _____.

Answer 11

Thin peptidoglycan layer

NAG and NAM

lipoteichoic acid

Question 12

The outer membrane of a gram-negative bacteria is a _______. Its inner layer is composed of _____ molecules and ____.

The outer layer of the outer membrane is composed of both _____ molecules and another molecule called _____ (__)

Answer 12

The outer membrane of a gram-negative bacteria is a __bilayer__. Its inner layer is composed of __phospholipid___ molecules and __proteins__.

The outer layer of the outer membrane is composed of both ___phospholipid __ molecules and another molecule called __lipopolysaccharide_(LPS)

Question 13

The lipid portion of LPS is known as _____ __ which is also called an ________ (this is released when the cell ____ and can cause fever, vasodilation, inflammation, shock, and blood clotting)

Answer 13

The lipid portion of LPS is known as LIPID A which is also called an ENDOTOXIN (this is released when the cell DIES and can cause fever, vasodilation, inflammation, shock, and blood clotting)

Question 14

Why are viruses often mistaken as _______s?

Answer 14

Mycoplasmas

They have an undefined shape (due to no cell wall)

Question 15

What’s the function of bacterial cell/cytoplasmic membranes

Answer 15

Maintains concentration gradient/water balance

Selectively permeable- very specifically regulates what goes in and out of the cell

Question 16

3 appendages can be found on the exterior of bacterial cell walls:

Answer 16

Flagella, Fimbraiea, Pili

Question 17

Flagella

Answer 17

Made up of proteins called flagellin

Used for movement

Basal body attaches hook to a cell wall and cell membrane

Question 18

Flagella arrangements

Answer 18

Monotrichous: one

Amphiritichous: two on opposite ends

Lophotrichous: 2+ on the same end

Peritrichous: all around/surrounding

Question 19

Flagella:
movement of bacteria towards or away from a particular stimulus is called ___. If the stimulus is a _____, the movement is called _______.

Answer 19

movement of bacteria towards or away from a particular stimulus is called TAXIS. If the stimulus is a CHEMICAL, the movement is called CHEMOTAXIS.

Question 20

Types of movement for flagella

Answer 20

Runs (propels foward): counterclockwise

Tumbles: Clockwise

Question 21

Fimbriae and pili are both used for _____ and are made up of protein molecules called ____. What’s the difference between the two?

Answer 21

Fimbriae and pili are both used for ATTACHMENT and are made up of protein molecules called PILINS.

Pili attachment is for a specific purpose called conjugation.

Question 22

Conjugation role in pili

Answer 22

Pili functions to transfer DNA from one cell to another with conjugation- known as sex pili

Question 23

Fimbriae vs Pili in terms of number

Answer 23

Fimbriae: ranges from a few to several hundred per cell

Pili: only one or two per cell

Question 24

The cytoplasm of bacteria contains the DNA in a ____ ___. The main organelle consistently present is ____.

Answer 24

nucleoid reigion

ribosomes

Question 25

Prokaryotes lack organelles, except for ____s. How are the ______s different from the ______s in eukaryotes?

Answer 25

Ribosomes

In prokaryotes, the size is 70S

In eukaryotes, the size is 80S

Question 26

Inclusions

Answer 26

Found in the cytoplasm of some bacteria

May include energy deposits (polyhydroxybutrate)

Has an industrial use for recyclable plastics

Question 27

Also found in the cytoplasm of some bacteria are ______ which are used as a ________ strategy against ______ _____, such as when nutrients (especially ___ and ___) are exhausted or if there isn’t sufficient _____.

Answer 27

Also found in the cytoplasm of some bacteria are ENDOSPORES which are used as a DEFENSE strategy against UNFAVORABLE CONDITIONS, such as when nutrients (especially Carbon and Nitrogen) are exhausted or if there isn’t sufficient MOISTURE.

Question 28

Where are endospores found?

Answer 28

Cytoplasm

Question 29

Endospores are formed by a process called _____ which takes between 8-10 ____. Endospores can remain dormant for thousands of years and when conditions become ___ for growth, endospores ___ to produce new _____ ___ (cells that _____ and ______).

Answer 29

Endospores are formed by a process called SPORULATION which takes between 8-10 HOURS. Endospores can remain dormant for thousands of years and when conditions become FAVORABLE for growth, endospores GERMINATE to produce new VEGETATIVE CELLS (cells that GROW and REPRODUCE).

Question 30

Steps in sporulation (endospores)

Answer 30

1) DNA replicates

2) Cytoplasm divides, forming forespore

3) Second cell membrane forms around forespore and original DNA deteriorates

4) Peptidoglucan cortex forms between cell membranes

5) Spore coat forms around the endospore

6) Endospore gets released

Question 31

Endospores are considered the _________________________ to ______. Many endospores produce toxins that can cause fatal diseases such as ____ and ____.

Answer 31

most difficult biological structure to destroy

anthrax and tetanus

Question 32

5 comparisons between bacterial (prokaryotic) and eukaryotic cells

Answer 32

Bacteria:
No nucleus
Flagella rotate
Cell walls (present in most) contain peptidoglycans
Endospores are present in some
Small (70S) ribosomes

Eukaryotes:
Nucleus
Flagella undulate
Cell walls- present in plants, algae, and fungi- NO peptidoglycans
No endospores
Large (80S) ribosomes in cytosol and smaller (70S) in mitochondria/chloroplasts

Question 33

In eukaryotes, the size of ribosomes is ____, except in ______ and ________ which are _____.

What theory describes what this is? Briefly describe it.

Answer 33

In eukaryotes, the size of ribosomes is 80S, except in mitochondria and chloroplasts which are 70S.

Endosymbiotic Theory- 2 prokaryotes: the larger anaerobic prokaryote ate the smaller aerobic prokaryote, forming a union (the eukaryote). The smaller one became an internal parasite and the larger cell became dependent on it for aerobic ATP production.

Question 34

In the Endosymbiotic Theory, the _____ prokaryote evolved into ______

Answer 34

The aerobic prokaryote evolved into mitochondria