Chapter 6

Question 1

What is Autotroph?

Answer 1

An organism that can form nutritional organic substances from simple inorganic substances such as carbon dioxide.

Question 2

Heterotroph

Answer 2

An organism deriving its nutritional requirements from complex organic substances

Question 3

Obligate aerobe

Answer 3

Obligate aerobic organisms are organisms that cannot grow (or survive) without a sufficient source of oxygen.

Question 4

Microaerophile

Answer 4

REQUIRE oxygen to live and have an electron transport chain.

Question 5

Acidophile

Answer 5

Microorganisms that thrive under acidic conditions, usually at very low pH (<3).

Question 6

Essential nutrient

Answer 6

Anything that an organism needs to have and can’t make for itself.

Question 7

Macronutrients

Answer 7

The nutrients we need in larger quantities that provide us with energy

Question 8

Micronutrients

Answer 8

Vitamins and minerals needed by the body in very small amounts.

Question 9

Phototrophs

Answer 9

Organisms that use light as their source of energy to produce ATP and carry out various cellular processes.

Question 10

Light energy

Answer 10

A form of energy consisting of particle-like photons with wavelike properties, and is which affects the physiology of organism.

Question 11

Chemotrophs

Answer 11

A class of organism that obtain their energy through the oxidation of inorganic molecules, such as iron and magnesium.

Question 12

Chemical source of energy

Answer 12

Biologic oxidation of these organic compounds by bacteria results in synthesis of ATP as the chemical energy source

Question 13

Growth limiting nutrient

Answer 13

There is not enough of the limiting nutrient to support ongoing growth on an exponential level, so this growth is restricted.

Question 14

Nitrogen fixation

Answer 14

A chemical process that converts atmospheric nitrogen into ammonia, which is absorbed by organisms.

Question 15

Nitrogen fixers

Answer 15

Prokaryotic microorganisms that are capable of transforming nitrogen gas from the atmosphere into “fixed nitrogen” compounds, such as ammonia, there are usable by plants.

Question 16

Optimum temperature

Answer 16

A temperature at which a maximum value of the average reaction rate has been obtained.

Question 17

Psychrophiles

Answer 17

An organism that is capable of living and thriving in temperature ranging from -20C to +10C

Question 18

Psychrotrophs

Answer 18

Cold tolerant bacteria or archaea that have the ability to grow at low temperatures, but have optimal and maximal growth temperatures above 15 and 208C.

Question 19

Mesophiles

Answer 19

An organism that grows best in moderate temperature, neither too hot nor too cold, with an optimum growth range from 20 to 45C (68 to 113F)

Question 20

Thermophiles

Answer 20

Organisms that grow at temperature above (25-40C) that sustain most life forms.

Question 21

Hyperthermophiles

Answer 21

Microorganisms that optimally grow at temperature above 80C

Question 22

Oxidizer

Answer 22

A substance that facilitates the process of oxidation in a chemical redox reaction by accepting electrons from another substance, which results in the reduction of the oxidizer.

Question 23

Reactive oxygen species

Answer 23

Oxygen containing radicals that are capable of independent existence with one or more unpaired electrons.

Question 24

Aerobes

Answer 24

An organism able to live and reproduce only in the presence of free oxygen.

Question 25

Obligate aerobes

Answer 25

An aerobe that requires oxygen for aerobic respiration.

Question 26

Facultative anaerobes

Answer 26

The organisms which can survive in both oxygenated as well at the deoxygenated environment.

Question 27

Fermentation

Answer 27

Another anaerobic (non-oxygen-requiring)pathway for breaking down glucose.

Question 28

Microaerophiles

Answer 28

An organism that lives in environment that only has a low level of oxygen.

Question 29

Anaerobes

Answer 29

Any organism that does not require molecular oxygen for growth.

Question 30

Obligate Anaerobes

Answer 30

Organisms that can grow and survive only in the absence of oxygen.

Question 31

Aerotolerant anaerobes

Answer 31

An organism that does not require oxygen for growth but can tolerate its presence.

Question 32

Neutrophiles

Answer 32

Important effector cells in the innate arm of the immune system.

Question 33

Alkaliphiles

Answer 33

Microorganisms that grow optimally or very well at pH values above 9 but cannot grow or grow only slowly at the near- neutral pH value of 6.5

Question 34

Acidophiles

Answer 34

The organism capable to inhabit strongly acidic habitats, which can reach really low pH value.

Question 35

Halophiles

Answer 35

Those microorganisms that require salt (NaCl) for growth)

Question 36

Basophiles

Answer 36

Type of white blood cell that works closely with your immune system to defend your body from allergens, pathogens and parasites.

Question 37

Binary fission

Answer 37

A type of asexual reproduction typically observed in prokaryotes and a few single-called eukaryotes.

Question 38

Generation time

Answer 38

The average time between two consecutive generations in the lineages of a population.

Question 39

Growth curve

Answer 39

A curve in graph form that shows the change in the number of cells (or single-called organisms) in an experimental culture at different times.

Question 40

Lag phase

Answer 40

Initial cell growth phase is generally characterized by metabolic activity but not growth

Question 41

Log phase

Answer 41

One of the phases observed in a bacterial growth curve.

Question 42

Stationary phase

Answer 42

The stage when growth ceases but cells remain metabolically active.

Question 43

Death phase

Answer 43

The point where the living cells stop metabolic functions and begin the process of death.

Question 44

Compare and contrast metabolic lifestyle of different organisms, and be able to determine into which category an organism belongs.

Answer 44

Different organisms have different metabolic lifestyles. Some organisms are autotrophs, which can produce their own food through photosynthesis or chemosynthesis. Others are heterotrophs, which obtain energy by consuming other organisms. By understanding an organism’s ability to produce its own food, we can determine whether it belongs to the autotroph or heterotroph category.

Question 45

Describe the flow carbon

Answer 45

The flow of carbon refers to the movement of carbon through various processes in the environment. Carbon is cycled through the atmosphere, plants, animals, and the Earth’s surface. It starts with carbon dioxide being taken in by plants during photosynthesis, where it is converted into organic compounds. Animals then consume these plants, obtaining carbon for their own growth and energy. When organisms die and decompose, carbon is released back into the environment. This continuous cycle of carbon flow helps maintain the balance of carbon in our ecosystem.

Question 46

Describe the flow of nitrogen

Answer 46

The flow of nitrogen involves various processes in the environment. Nitrogen is present in the atmosphere as nitrogen gas (N2), which cannot be directly used by most organisms. Nitrogen fixation is the process by which certain bacteria convert nitrogen gas into a usable form, such as ammonia (NH3) or nitrate (NO3-). This fixed nitrogen is then taken up by plants and used to build proteins and other essential molecules. Animals obtain nitrogen by consuming plants or other animals. When organisms die or produce waste, nitrogen is returned to the environment through decomposition. Denitrification is another process where certain bacteria convert nitrate back into nitrogen gas, completing the nitrogen cycle. This continuous flow of nitrogen is crucial for the growth and development of living organisms.

Question 47

Describe the flow of energy in an ecosystem

Answer 47

Energy flows through different trophic levels in an ecosystem. Producers, like plants, capture energy from the sun through photosynthesis. This energy is then transferred to primary consumers, which are herbivores that eat plants. The energy continues to flow through the ecosystem as secondary consumers, which are carnivores that eat herbivores, and tertiary consumers, which are carnivores that eat other carnivores. Energy is also lost as heat at each trophic level and through metabolic processes. Decomposers break down dead organisms, releasing energy back into the ecosystem. Overall, energy flows from the sun to producers, and then through various consumers and decomposers, sustaining life in the ecosystem.

Question 48

5. Identify the environmental requirements of different organisms in terms of oxygen, temperature, pressure, salinity, and pH

Answer 48

Different organisms have specific environmental requirements for oxygen, temperature, pressure, salinity, and pH. For example, some organisms require high oxygen levels, while others can survive in low-oxygen environments. Similarly, temperature preferences vary among organisms, with some thriving in cold environments and others in warmer ones. Pressure requirements differ as well, with certain organisms adapted to high-pressure environments, such as deep-sea creatures. Salinity tolerance varies, with some organisms adapted to freshwater habitats and others to saltwater environments. Lastly, pH preferences range from acidic to alkaline, with organisms adapted to specific pH levels. Each organism has its own unique set of requirements to thrive in its environment.

Question 49

What are the 4 phases of growth curve?

Answer 49

1) Lag phase
2) Log phase
3) Stationary phase
4)Death phase