September 16

Question 1

Gliding motility

Answer 1

Does not use flagella

Smooth and slower than flagella

Requires contact with a surface

Excrete polysaccharide slime (can glide on agar)

Some cyanobacteria

Question 2

Microbial Taxis Types

Answer 2

Directed movement in response to a stimulus

1. Chemotaxis: movement in response to a chemical
2. Phototaxis: movement in response to light
3. Aerotaxis
4. Hydrotaxis:

Question 3

Describe E. coli’s taxis

Answer 3

“run and tumbe”

Peritrichous flagellar arrangement

Attractants sensed by chemoreceptors on cell

Question 4

Define metabolism

Answer 4

All biochemical reactions in a cell

Question 5

Catabolic

Answer 5

breaks down larger molecules into smaller molecules, exogonic

Question 6

Anabolic

Answer 6

Smaller molecules are built into larger ones, endogonic

Question 7

Macronutrients

Answer 7

Nutrients needed in large amounts

Ex. Carbon

Question 8

Micronutrients

Answer 8

required in small amounts

Ex. iron

Question 9

Why do cells need nitrogen?

Answer 9

Growth-limiting

required for proteins, nucleic acids

Question 10

Why do cells need phosphorus?

Answer 10

Nucleic acids and phospholipids

Question 11

Why do cells need sulfur?

Answer 11

Some amino acids contain sulfur

Also in vitamins

Question 12

Why do cells need potassium?

Answer 12

Some enzymes require K+

Question 13

Why do cells need magnesium?

Answer 13

Stabilizes cell membrane, ribosomes, nucleic acids

Question 14

Why do cells need calcium?

Answer 14

Stabilizes cell walls, Ca²⁺ heat stability of endospore

Question 15

Why do cells need iron?

Answer 15

It plays a role in e- transport

Question 16

Enzymes

Answer 16

Biological catalyst, lowers the activation energy of a reaction

increase reaction rate

Reactions would occur even without enzymes

Usually proteins, some are RNA these are called riboenzymes

Question 17

Apoenzyme

Answer 17

Protein portion of the enzyme

Question 18

Cofactor enzymes

Answer 18

Bind to apoenzyme, without them the enzyme is nonfunctional

Question 19

Haloenzyme

Answer 19

Apoenzyme plus cofactors/coenzymes

Question 20

Active Site

Answer 20

Location on an enzyme where the substrate binds

Question 21

Allosteric Site

Answer 21

Site other than the active site

Where inhibitors or activators bind

Question 22

Affect of temperature on enzymatic activity

Answer 22

In most chemical reactions the rate of reaction tends to increase with an increase in temperature.

In enzymatic reactiions, temperatures above optimal cause denaturation

Question 23

Affects of pH on Enzymes

Answer 23

Denaturation occurs above and below optimal pH

Question 24

Affects of Substrate Concentration on Enzyme Activity

Answer 24

Saturation point: all enzymes are bound to substrate, activity levels off

Question 25

Redox Reactions

Answer 25

How energy is conserved in cells Conserving energy in synthesis of energy-rich compounds (ATP) Electron-donor is oxidized Electron-acceptor is reduced

Question 26

Energy Carriers

Answer 26

NAD+ FAD+ NADPH

Question 27

Chemoorganotroph

Answer 27

Two reaction series involved in energy conservation: Fermentation and respiration, differ in mechanism of ATP synthesis

Question 28

Substrate-Level Phosphorylation

Answer 28

Fermentation ATP is made from energy-rich intermediate

Question 29

Oxidative Phosphorylation

Answer 29

Electron Transport Chain

Question 30

Glycolysis

Answer 30

First step of both fermentation and cellular respiration Three stages **Net Yeild of ATP per molecule of glucose:** 2 Produces 4 ATP, but 2 ATP are used in energy investment stage 2 Net 4 produced 2 used