Microbial Nutrition And Growth

Question 1

Organisms use a variety of chemicals called nutrients to meet their energy needs and to build organic molecules and cellular structure the most common of these nutrients are compounds containing necessary elements such as

Answer 1

Carbon, oxygen, nitrogen, and hydrogen

Question 2

define autotrophs

Answer 2

Organisms that utilize and in the organic source of carbon as their sole source of carbon

Question 3

Define heterotrophs

Answer 3

Cataba lies reduced organic molecules such as proteins they acquire from other organisms

Question 4

Define phototrophs

Answer 4

Organisms that use light as their energy source

Question 5

Define chemotrophs

Answer 5

Organisms that acquire energy from redox reaction including inorganic and organic chemicals

Question 6

Define Organotrophs

Answer 6

Hetero trough’s acquire electrons from the same organic molecules that provide them carbon

Question 7

Define lithotrophs

Answer 7

Autotrophic organisms acquire electrons or hydrogen atoms from inorganic molecules

Question 8

Obligate aerobes

Answer 8

Oxygen is essential because it serves as the final electronic scepter of electron transport chain which produced most of the ATP in these organisms

Question 9

Obligate anaerobes

Answer 9

Cannot use oxygen to produce ATP

Question 10

Singlet oxygen

Answer 10

Is molecular oxygen with electrons that have been posted to a higher energy state typically during aerobic metabolism

Question 11

Superoxide radical (O2-)

Answer 11

A few superoxide radicals form during the incomplete reduction of 002 during electron transport in aerobes and during metabolism by anaerobes in the presence of oxygen

Question 12

Peroxide anion

Answer 12

Hydrogen peroxide form during reactions catalyzed by super oxide dismutase contains peroxide and ion another highly reactive oxidant

Question 13

Nitrogen

Answer 13

Is often a growth limiting nutrient for many organisms that is their anabolism seizes because they do not have sufficient nitrogen to build proteins and nucleotides

Question 14

Nitrogen fixation

Answer 14

As essential for life on earth because nitrogen fixers provide nitrogen in a usable form two other organisms

Question 15

Psychrophiles

Answer 15

Grow best at temperatures below about 15°C and can even continue to grow at temperatures below 0°C

Question 16

Mesophiles

Answer 16

Organisms that grow best in temperatures ranging from 20°C to about 40°C because they can’t survive at higher and lower temperatures. Human pathogens are mesophiles

Question 17

Thermophiles

Answer 17

Grow at temperatures above 45°C and habitats such as compost pile’s and Hot Springs

Question 18

Hyperthermophiles

Answer 18

Grow in water above 80°C others live at temperatures above 100°C

Question 19

Neutrophiles

Answer 19

Grow best in between pH 6.5 MPH 7.5 which is also the pH range of most tissues and organs in the human bodies

Question 20

Acidophiles

Answer 20

Organisms that grow best in acidic habits

Question 21

Alkalinophiles

Answer 21

Live in alkaline soil and water up to PH 11.5

Question 22

Lag Phase

Answer 22

The cells are adjusting to their new environment most cells do not reproduce immediately but instead actively synthesize enzymes to utilize novel nutrients

Question 23

Log phase

Answer 23

Eventually the bacteria synthesize the necessary chemicals for conducting metabolism in their new environment and then they enter a phase of rapid chromosome replication growth and reproduction

Question 24

Stationary Phase

Answer 24

Eventually the number of dying cells equals the number of cells being produced and the size of the population remains constant

Question 25

Death Phase

Answer 25

If nutrients are not added and wastes are not remove a population reaches a certain point at which cells die at a faster rate than they are produced