Fundamentals Of Microbiology - Cells, Metabolism, and Growth

Question 1

What characteristics distinguish living organisms?

Answer 1

1. Responsiveness
2. Growth
3. Reproduction
4. Metabolism
5. Movement
6. Excretion
7. Cell

Question 2

What are Prokaryotes?

Answer 2

Bacteria + Archaea

Question 3

What distinguishes prokaryotes from eukaryotes?

Answer 3

• No nuclear membrane
• No membrane bound organelles
• No cell nucleus
• Ribosomes - protein synthesis, not really an organelle

Question 4

How small are prokaryotes?

Answer 4

Smaller (0.5 - 5 micrometers)

Question 5

What distinguishes a eukaryote cell from a prokaryote?

Answer 5

• Nucleolus
• Vesicle
• Endoplasmic reticulum
• Golgi apparatus
• Centrioles
• Algae and plants contain organelles (chloroplasts) for photosynthesis with coloured pigments to trap sunlight energy

Question 6

What do cells need for growth?

Answer 6

• Energy
• Electrons
• Matter - carbon, substrates, minerals

Question 7

What is catabolism?

Answer 7

Catabolism = cellular energy production → energy release
- creates simple molecules

Question 8

What is anabolism?

Answer 8

Anabolism = assimilation, growth, and repair → energy consumption
- new cellular materials are made larger

Question 9

What allows metabolism to take place?

Answer 9

Metabolism = catabolism + anabolism + enzyme catalysts

Question 10

What are some characteristics of catabolism?

Answer 10

• Produce simple waste
• Energy temporarily conserved as ATP

Question 11

What are some characteristics of anabolism?

Answer 11

Anabolism is characterized by energy consumption, the synthesis of complex molecules from simpler ones, and its role in growth and repair of body tissues.

Question 12

What are autotrophs?

Answer 12

Cells that use inorganic carbon - CO2 - autotrophic

Question 13

What are chemoautotrophs?

Answer 13

An organism, typically a bacterium, which derives energy from the oxidation of inorganic compounds

Question 14

What are Photoautotrophs?

Answer 14

Organisms that carry out photosynthesis. Use light as an energy source

Question 15

What are heterotrophs?

Answer 15

Consume organic matter and break it up

Question 16

What are chemoheterotrophs?

Answer 16

Microbes that get their energy from organic chemicals and mainly use organic compounds for carbon (fungi+animals)

Question 17

What are photoheterotrophs?

Answer 17

Group of microorganisms acquires energy from sunlight - purple nonsulfur bacteria

Question 18

What does ATP stand for?

Answer 18

Adenosine triphosphate

Question 19

What is the first thing that happens to glucose molecule in catabolism and energy production?

Answer 19

Glycolysis - no oxygen need

Question 20

What comes after glycolysis?

Answer 20

Pyruvate

Question 21

What happens in the presence of oxygen in the process of catabolism and energy production?

Answer 21

• Taken into mitochondria
• Where it goes through the Kreb cycle and more ATP created

Question 22

What creates more ATP?

Answer 22

The electron transport chain

Question 23

What happens in anaerobic conditions in catabolism and energy production?

Answer 23

Fermentation which causes lactate

Question 24

What happens in the Kreb cycle?

Answer 24

A series of reactions releasing ATP from citric acid breakdown

Question 25

What happens in the electron transport chain?

Answer 25

Couples a series of chemical reactions between an electron donor (e.g., NADH) and an electron acceptor (e.g., O2); H+ ions and electrons are used to produce ATP

Question 26

What must cells do when oxygen absent?

Answer 26

Must use an alternative terminal electron acceptor to complete the catabolic process

Question 27

How can H+ ions travel from high con to low con?

Answer 27

ATP Synthase

Question 28

What causes new growth in cells

Answer 28

Substrate and enzyme production

Question 29

What is the specific growth constant?

Answer 29

mu

Question 30

When does growth rate decline to zero?

Answer 30

As substrate exhausted

Question 31

How does cell division happen in prokaryotes?

Answer 31

- Prokaryotes - binary fission → no spindle apparatus for dividing chromosomes - Divide every 20 - 30 min - Similar to asexual mitosis

Question 32

What cell division happens in eukaryotes?

Answer 32

Mitosis and Meiosis

Question 33

How can pH affect growth?

Answer 33

Effects enzyme activity and protein structure

Question 34

What are the different types of organism which can survive different pHs?

Answer 34

Acidophiles, Alkaliphiles, Neutrophiles

Question 35

What are the different types of organisms which can tolerate different temps?

Answer 35

- Thermophile tolerate highest temperatures (40-80 degrees) - Mesophile - Psychrophile

Question 36

What are facultative anaerobes?

Answer 36

- Do not require free O2 for growth, but grow better in its presence - Have genes for both respiration + fermentation

Question 37

What are obligate aerobes?

Answer 37

Can only grow in the presence of O2

Question 38

What are obligate anaerobes?

Answer 38

- Cannot tolerate the presence of O2 and die when exposed to it - Only use alternative electron acceptors

Question 39

How does water affect growth?

Answer 39

- Cells sensitive to changes in osmotic potential - Cell walls maintain cell integrity - Salinity or drying prevent microbial growth

Question 40

What is osmosis?

Answer 40

Water molecules move from region of high kinetic energy to lower kinetic energy, randomly passing through the semi-permeable membrane; solute molecules are too large to pass through the semi permeable membrane