Microbiology Ch. 6

Front 1

_____ catalyze all cellular reactions

Back 1

enzymes

Front 2

_____ increase the probability that chemicla reactions will occur

Back 2

enzymes

Front 3

_____ are not changed by the reactions, and can be reused

Back 3

enzymes

Front 4

______ activity is highly specific

Back 4

enzyme

Front 5

_____ act on substrates

Back 5

enzymes

Front 6

______ lower the activation energy so a reaction is more likely to occur

Back 6

enzymes

Front 7

_____ weaken chmeical bonds in the substrate

Back 7

Enzymes

Front 8

____ ____ = Lock and Key model

Back 8

Old model
(perfect fit)

Front 9

____ ____ = substrate, active site, product

Back 9

Induced fit
(not perfect, like a temperpedic mattress it forms to fit the body)

Front 10

____ can be named in one of two ways
- by thier function
- by the sbustrate on which they act
* Examples:
- sucrase
- lipase
- oxidase
- hydrolase

Back 10

Naming enzymes

Front 11

_____ act thorugh enzyme-substrate complexes

Back 11

Enzymes

Front 12

_____ align substrate molecules in such a way that a reaction is energetically favorable

Back 12

Enzymes

Front 13

______ bind to the enzyme at the active site, which is specific to the substrate

Back 13

Substrates

Front 14

____ lower the activation energy so a reaction is more likely to occur

Back 14

Enzymes

Front 15

Enzymes weaken chemical bonds in the ______

Back 15

substrate

Front 16

____ can:
- be made entirely of protein or
- have a complementing substance, such as:
- a metal ion (cofactor)
- an organic molecule (coenzyme)

Back 16

Enzymes

Front 17

Carbonic Anhydrase
* The gray sphere is zinc ( a metal) acting as a _____

Back 17

cofactor

Front 18

______- a subclass of cofactors that are organic molecules (but not proteins)
* Ascorbic acid - Vitamin C acts as an electron carrier

Back 18

Coenzymes

Front 19

____ often team up in metabolic pathways

Back 19

enzymes

Front 20

A metabolic pathway is a sequence of _____ _____
- each reaction is catalyzed by a different enzyme
- the product of one reaction serves as the substrate for the next

Back 20

chemical reactions

Front 21

Enzyme activity is regulated and can be _____

Back 21

inhibited

Front 22

_____ inhibition hinders metabolic pathways
- it inhibits an enzyme in the pathway so no product is available to feed the next reaction

Back 22

feedback

Front 23

Other types of _____ include
- changing the shape of an active site (noncompetitive inhibition)
- blocking an active site (competitive inhibition)

Back 23

inhibition

Front 24

Energy in the form of ____ is required for metabolism

Back 24

ATP

Front 25

____ is the cellular "energy currency," providing energy for:
- movement
- cell division
- protein synthesis, etc.

Back 25

ATP

Front 26

_____ is released from ATP when the bond holding the last phosphate group on the molecule is broken, producing
- adenosine diphosphate (ADP)
- a free phosphate group

Back 26

Energy

Front 27

Adding a phosphate group to a molecule is called ______

Back 27

phosphorylation

Front 28

Enzymes that transfer a phosphate from one molecule to another are called _____

Back 28

kinases

Front 29

_____ cannot be stored because it is relatively unstable
- energy must be stored in more stable forms like glycogen, starch or lipids (in prokaryotes), which can then be used to form ATP

Back 29

ATP

Front 30

_____ contains stored energy that can be extracted

Back 30

Glucose

Front 31

_____ in glucose is released slowly by converting to ATP through metabolic pathways

Back 31

Energy

Front 32

Cellular respiration is a series of catabolic pathways for the production of _____

Back 32

ATP

Front 33

Cells make ____ by harvesting energy through cellular respiration

Back 33

ATP

Front 34

If oxygen is consume while making ATP, it is ______ respiration

Back 34

aerobic

Front 35

Major _____ pathways break organic molecules down - use harvested potential energy to form ATP

Back 35

Catabolic

Front 36

Formation of ATP in a cell =

Back 36

respiration

Front 37

Name the two major Catabolic Pathways

Back 37

Fermentation and Aerobic respiration
- both start with glycolysis

Front 38

Catabolic Pathways: an overview
_______
- a 10 step pathway
- aerobic resp. and ferm. both start here
- all steps are catalyzed by enzymes
- does not require oxygen or specialized membranes
- occurs in the cytoplasm
- all cells do this
- because of last 3 items, is viewed as an ancient pathway

Back 38

Glycolosis

Front 39

Catabolic pathways overview, cont..
_______ _______
- is comprised of 2 pathways
- Kreb's Citric Acid Cycle
- an electron transport system
- it follows glycolysis
- requires oxygen, special membranes, special electron transporting proteins
- because of last 2 items, is viewed as a more recent pathway

Back 39

Aerobic Respiration

Front 40

Step 1 in Aerobic Respiration or Fermentation:
______
-______ splits 1 glucose molecule into 2 pyruvate molecules
- steps 1-3= energy requiring reactions
- step 4 = molecule breaks in half
- Steps 5-10 = energy harvesting reactions

Back 40

Glycolysis

Front 41

Net yield for _____ is 2 ATP; 2 NADH - is a carrier molecule that gives you lots of energy

Back 41

Glycolysis

Front 42

Aerobic Respiration, Cont:
____ _____ ____ ____
The ____ ____ extracts additional energy from pyruvate following glycolysis
- synthesizes "building block" molecules
- before entering ___ ____, pyruvate molecules coming from glycolysis must pass through an intermediate step

Back 42

Kreb's Citric Acid Cycle

Front 43

The Krebs Cycle Extracts more energy from ______

Back 43

Pyruvate

Front 44

The krebs cycle is also called the ____ ____ ____

Back 44

Citric Acid Cycle

Front 45

Before entering the Krebs cycle, ______:
- remove a carbon from each pyruvate molecule
- combine the carbon with coenzyme A (CoA) to form acetyl - CoA
- This releases 2 NADH and 2 CO2

Back 45

enzymes

Front 46

For each two _____ molecules that enter the cycle, the following molecules are formed
- 4 CO2
- 2 ATP
- 6 NADH
- 2 FADH2

Back 46

pyruvate

Front 47

Oxidative Phosphorylation is the process by which most ____ molecules form

Back 47

ATP

Front 48

Pair of _____ are passed from one chemical substance to another (electron transport), releasing energy

Back 48

electrons

Front 49

The energy released is used to combine phosphate with ADP to form _____

Back 49

ATP

Front 50

The electron transport chain is composed of electron carriers called _____

Back 50

cytochromes

Front 51

NADH and FADH2 provide the source electrons for _____ ____

Back 51

oxidative phosphorylation

Front 52

______ accepts the electron pair at the end of the chain acquires 2 protons, and becomes water

Back 52

Oxygen

Front 53

As the _____ move down the chain they use energy, which is harnessed to pump protons out of the cell (chemiosmosis)

Back 53

electrons

Front 54

The _____ outside the membrane build up a concentration gradient

Back 54

protons

Front 55

A channel opens and the ____ flow in through a channel in ATP synthesis

Back 55

protons

Front 56

ATp synthase harnesses the energy from the flowing protons to phosphorylate ADP into ____

Back 56

ATP

Front 57

Many mono-, di-, and polysaccharides can be energy sources for ______

Back 57

prokaryotes

Front 58

Chemical bonds in ____ store large amounts of energy, making ____ good energy sources

Back 58

fats

Front 59

Cells use _____ for energy when fats and carbohydrates are lacking

Back 59

proteins

Front 60

______ is the replacement of the amino group in a protein with a carbonyl group in protein breakdown

Back 60

Deamination

Front 61

Fatty acids are broken down through _____ _____

Back 61

beta oxidation

Front 62

______ respiration produces ATP using other final electron acceptors

Back 62

Anaerobic

Front 63

In _____ respiration, _____ use molecules other than oxygen as the final electron receptor in the electron transport chain

Back 63

Anaerobic

Front 64

Anaerobic respiration produces less ____ than aerobic respiration

Back 64

ATP

Front 65

______ produces ATP using an organic final electron receptor

Back 65

fermentation

Front 66

______ is used when oxygen and other alternative electron acceptors are unavailable

Back 66

Fermentation

Front 67

______ can be converted to lactic acid to reform NAD+ coenzymes so glycolysis can produce ATP from glucose

Back 67

Pyruvate

Front 68

Fermentation Pathway
* Pyruvate ----
- In our muscle cells

Back 68

Lactate

Front 69

Fermentation Pathway
* Pyruvate ------
- in yeast cells
- used commercially to produce risen bread and alcoholic beverages

Back 69

CO2 + ethanol

Front 70

______ can be identified by their fermentation product

Back 70

Prokaryotes

Front 71

______ respiration produces ATP using other final electron acceptors

Back 71

Anaerobic

Front 72

______ is a process to acquire chemical energy

Back 72

Photosynthesis

Front 73

In ______, light energy is converted to chemical energy, which is stored as an organic compound

Back 73

photosynthesis

Front 74

In prokaryotes photosynthesis is carried out in the cell membrane, in eukaryotes in organelles called _______

Back 74

chloroplasts

Front 75

The gree pigment _____ absorbs light energy

Back 75

chlorophyll

Front 76

Some bacteria use other pigments, such as _________
- some archaea use bacteriorhodopsin

Back 76

bacteriochlorophylis

Front 77

______ is divided into two sets of reactions
- energy-fixing reactions:
- carbon-fixing reactions

Back 77

Photosynthesis

Front 78

The Carbon-Fixing Reaction

Back 78

The Calvin Cycle

Front 79

_____ and heterotrophs get their energy and carbon in different ways

Back 79

Autotrophs

Front 80

_____ synthesize their own foods from simple carbon sources like carbon dioxide

Back 80

Autotrophs

Front 81

_______ use light as their energy source

Back 81

photoautotrophs

Front 82

_____ feed exclusively on dead organic matter-mold

Back 82

Saprobes

Front 83

The microbial ant foe is called Thelohania solenopsae is a protozoan _____; live on living material

Back 83

Parasite