Module 4 Growth & Nutrition EXAM 2

Question 1

What are the four basic elements (C,H,O, and N) necessary for proper nutrition and how organisms obtain them and utilize them?

Answer 1

The four elements CHON are Carbon, Hydrogen, Oxygen, and Nitrogen are necessary for proper nutrition. ALL ARE UTILIZED to make up our organic compounds like proteins, lipids, carbohydrates, nucleic acids

Question 2

Where phosphorus is found?

Answer 2

Found in ATP
Found in nucleotides
Phospholipids found in cell membranes

Question 3

What are the four basic organic macromolecules that all organisms possess?

Answer 3

Proteins, Lipids, Carbohydrates, Nucleic Acids

Question 4

What is an autotroph?

Answer 4

Autotroph: (self-feeder) can obtain essential nutrients on their own, not nutritionally dependent on other living things, uses inorganic C02 as its carbon source = converts into organic form of carbon

Question 5

What is a heterotroph?

Answer 5

Heterotroph: must obtain essential nutrients from something else; nutritionally dependent on other living things

Question 6

What is a saprobes is and examples of saprobes?

Answer 6

A saprobe is a decomposer of dead plants, animals, and microbes; they release enzymes to the environment that externally digest food particles
Examples: fungi, some bacteria (decomposers)

Question 7

Passive transport is:

Answer 7

Substances move along their concentration gradient, from an area of higher concentration to an area of lower concentration, without requiring energy. Ex: Diffusion, Facilitated Diffusion, and Osmosis

Question 8

Active transport is:

Answer 8

Substances move against their concentration gradient, from an area of lower concentration to an area of higher concentration, requiring energy. Ex: Endocytosis & Exocytosis

Question 9

Diffusion

Answer 9

Active or Passive: Passive

Require ATP: NO

Types of molecules it carries out: Limited to small, nonpolar molecules

Movement: Down the concentration gradient

Question 10

Facilitated Diffusion

Answer 10

Active or Passive: Passive

Require ATP: NO

Types of molecules it carries out: Used to transport hydrophilic molecules

Movement: Down the concentration gradient through a protein channel or protein carrier (specific)

Question 11

Osmosis

Answer 11

Active or Passive: Passive

Require ATP: NO

Types of molecules it carries out: water molecules

Movement: Movement of water to where there are more solutes

Question 12

Endocytosis

Answer 12

(include pinocytosis and phagocytosis), active transport that requires energy, particles are engulfed into the cell

Question 13

Exocytosis

Answer 13

active transport that requires energy, package and release substances out of the cell

Question 14

Phagocytosis

Answer 14

“eating”; process carried out by white blood cells to engulf cells or particles (part of endocytosis in active transport)

Question 15

Pinocytosis

Answer 15

“drinking”; liquids entering the cell
(part of endocytosis in active transport)

Question 16

Psychrophile

Answer 16

Likes it COLDEST ❄️
Example: “Red Snow”: a type of algae that has a red pigment

Range: (-15)-15 degrees celsius

Question 17

Psychrotroph

Answer 17

Likes it colder but not as cold
Range: 15 - 35 degrees celsius

Question 18

Extreme Thermophile

Answer 18

Likes it the HOTTEST 🔥
Range: 70 - 130 degrees celsius

Question 19

Thermophile

Answer 19

Likes it hotter but not as hot
Range: 45 - 80 degrees celsius

Question 20

Mesophile

Answer 20

Grows at intermediate temperatures
Inhabit human body
Majority of pathogenic microbes in humans 🤒
(natural microbiome)

Range: 10 - 50 degrees celsius (humans at 37)

Question 21

Facultative anaerobe

Answer 21

capable of growth in the absence of oxygen

Question 22

Obligate aerobe

Answer 22

can NOT grow without oxygen

Question 23

Obligate anaerobes

Answer 23

will die if exposed to oxygen

Question 24

Microbial associations can be

Answer 24

symbiotic or nonsymbiotic

Question 25

Symbiotic

Answer 25

organisms live in close nutritional relationships; required by one or both members
Ex: Mutualism, Commensalism, Parasitism

Question 26

Parasitism

Answer 26

parasite is dependent and benefits; host is harmed

Question 27

Mutualism

Answer 27

obligatory, dependent (both organisms need the relationship); both members benefit

Question 28

Commensalism

Answer 28

commensal benefits; one needs relationship, other is not harmed

Question 29

Nonsymbiotic

Answer 29

organisms are free-living; relationships are not required for survival
Ex: Synergism, Antagonism

Question 30

Synergism

Answer 30

members cooperate and share nutrients; work together

Question 31

Antagonism

Answer 31

some members are inhibited or destroyed by others; don’t need or require each other so one member destroys the other

Question 32

What is the basic process of binary fission?

Answer 32

-Bacteria use binary fission to reproduce
-An asexual process: no exchange of genetic information-make exact copies
-Think of binary fission as simple mitosis; start with 1 circular chromosome that replicates and new and old chromosomes move to different sides of the cell and so on

OR

Another explanation a single parent cell duplicates its genetic material and then divides into two identical daughter cells. The steps typically involve the replication of the DNA, elongation of the cell, and the formation of a septum that separates the two new cells

Question 33

What is meant by a generation or doubling time and what the average time is for most bacteria?

Answer 33

Generation or doubling time: the time required for a complete fission cycle; each new fission cycle doubles the population
So for example: 0, 2, 4, 8, 16, 32… and so on
This growth pattern is termed exponential (log rhythmic scale)

Average generation time is 30-60 minutes, can be as short as 10-12 minutes

Question 34

What are the basic stages in a bacterial growth curve?

Answer 34

A population of bacteria does not maintain its potential growth rate and double endlessly; it displays a predictable growth pattern called a growth curve

Lag phase (can’t really see a difference)
Exponential Growth Phase (log phase)
Stationary Growth Phase (plateaus)
Death Phase (organisms begin to die off)