Bio Ii

Front 1

Why is cellular respiration dehydrogenation?

Back 1

Because electrons are accompanied by protons, so what is really lost is a hydrogen atom

Front 2

What is photosynthesis

Back 2

Converting radiant energy into chemical into chemical energy

Front 3

What are autotrophs

Back 3

Organisms that convert radiant energy into chemical energy "self feeders"

Front 4

What are heterotrophs?

Back 4

Organisms that live on the organic compounds ie autotrophs

Front 5

The process by which energy is harvested

Back 5

Cellular respiration

Front 6

What is thermodynamics?

Back 6

The branch of chemistry concerned with energy changes

Front 7

________ is defined as the capacity to do work

Back 7

Energy

Front 8

What are the 2 states of energy?

Back 8

1. Kinetic

2. Potential

Front 9

Describe kinetic energy.

Back 9

The energy of motion

Front 10

What is potential energy?

Back 10

Stored energy

Front 11

What are some forms that energy can take?

Back 11

Mechanincal, heat, sound, electric current, light or radioactivity

Front 12

What is the most convenient way to measure energy?

Back 12

Heat; bc all other forms of energy can be converted into heat

Front 13

What is the most common unit of heat?

Back 13

the kilocalorie (kcal)

Front 14

What is 1 calorie?

Back 14

the heat required to raise the temperature of 1 gram of water one degree celsius

Front 15

What is activation enegery?

Back 15

The energy required to destabilize existing chemical bonds and initiate a chemical reaction

Front 16

The rate of an exergonic reaction can be increased by lowering the ___________ energy required to destroy chemical bonds in the reactants

Back 16

activation

Front 17

Why do catalyst increase the rate of a chemical reaction

Back 17

catalyst stabilize the transition state in a reaction

Front 18

What type potential energy is stored within the covalent bonds of molecules?

Back 18

Chemical

Front 19

Fats are useful as energy storage molecules because they contain

Back 19

Many C-H bonds

Front 20

During oxidation of a molecule the net charge_________. Adding electrons during reduction __________the net charge of a molecule

Back 20

1. increases

2. reduces

Front 21

What are substrates?

Back 21

The molecule that will undergo the reaction

Front 22

How does an enzyme lower the activation energy required for new bonds to form

Back 22

By bringing two substrates together in the correct orientation or by stressing particular chemical bonds of a substrate

Front 23

The _________ itself is not changed or consumed in a reaction, only a small amount of it is needed and it can be used over and over

Back 23

Enzyme

Front 24

Give an example of how an enzyme assist in the rate of a reaction

Back 24

The reaction of carbon dioxide and water to form carbonic acid.

This reaction may proceed in either direction, but because it has a large activation energy, the reaction is very slow in the absence of an enzyme: Perhaps 200 molecules of carbonic acid form in an hour in a cell in the absence of any enzyme. Reactions that proceed this slowly are of little use to a cell. Vertebrate red blood cells overcome this problem by employing an enzyme within their cytoplasm called carbonic anhydrase (enzyme names usually end in “–ase”). Under the same conditions, but in the presence of carbonic anhydrase, an estimated 600,000 molecules of carbonic acid form every second! Thus, the enzyme increases the reaction rate by more than one million times

Front 25

What are active sites?

Back 25

The region of an enzyme surface to which a specific set of substrates binds, lowering the activation energy required for a particular chemical reaction and so facilitating it.

Front 26

Most ________are globular proteins with one or more pockets or clefts called____________ on their surface

Back 26

1. enzymes

2. Active sites

Front 27

What are the steps to enzyme-catalyzed reactions?

Back 27

1. Binding of substrate to active site

2. Catalytic step

3. Release of products

Front 28

Where are enzymes typically found when not in use

Back 28

suspended in the cytoplasm

Front 29

What is a multienzyme complex

Back 29

Several enzymes catalyzing different steps of a sequence of reactions; associated with one another in noncovalently bonded assemblies

Front 30

What multi enzyme complex catalyzes the oxidation of pyruvate?

Back 30

pyruvate dehydrogenase

Front 31

Multienzyme complexes offer the following significant advantages in catalytic efficiency:

Back 31

1.The rate of any enzyme reaction is limited by how often the enzyme collides with its substrate

2. Because the reacting substrate doesn’t leave the complex while it goes through the series of reactions, unwanted side reactions are prevented.

3.All of the reactions that take place within the multienzyme complex can be controlled as a unit.

Front 32

What is the function of pyruvate dehydronase

Back 32

To oxidize pyruvate

2. control entry into the Krebs cycle during aerobic respiration

Front 33

What is the function of the fatty acid synthase complex?

Back 33

catalyzes the synthesis of fatty acids from two carbon precursors.

--made up of 7 different enzymes

Front 34

What is a function of ribozymes

Back 34

They are RNA catalyst that greatly accelerated the rate of particular biochemical reactions

--show extraordinary substrate specificity

Front 35

_________ ___________catalyze reactions on themselves

Back 35

intramolecular catalysis

Front 36

________ ________act on other molecules without being changed themselves

Back 36

intermolecular catalysis

Front 37

What affects the rate of an enzyme-catalyzed reaction?

Back 37

1. the concentrations of both the substrate and the enzyme that works on it

2. any chemical or physical factor the at alters the enzyme's 3-dimensional shape (temp, pH, binding of regulatory molecules)

Front 38

Why does increasing the temperature of an uncatalyzed reaction increase the rate?

Back 38

BC the additional heat increases random molecular movement

---the motion can add stress to molecular bonds and affect the activation energy of a reaction

Front 39

What is optimum temperature?

Back 39

The maximum point at which the rate of an enzyme catalyzed reaction increases with temperature

Front 40

Why is the optimum temperature important in enzyme catalyzed reactions?

Back 40

Below this temperature, the hydrogen bonds and hydrophobic interactions that determine the enzyme’s shape are not flexible enough to permit the induced fit that is optimum for catalysis. Above the optimum temperature, these forces are too weak to maintain the enzyme’s shape against the increased random movement of the atoms in the enzyme. At higher temperatures, the enzyme denatures

Front 41

Most human enzymes have an optimum temperature between _____ and _________

Back 41

35 C and 40 C

Front 42

What ts the optimum temperature for most enzymes in prokaryotes that live in hot springs?

Back 42

70 C or higher

Front 43

Ionic interactions between oppositely charged amino acid residues such as ___________acid (-) and ___________ (+) also hold enzymes together

Back 43

a. glutamic

b. lysine

Front 44

why are Ionic interactions between oppositely charged amino acid residues sensitive to the hydrogen ion concentration of the fluid in which the enzyme is dissolved

Back 44

because changing that concentration shifts the balance between positively and negatively charged amino acid residues

Front 45

What is the typical optimum pH of enzymes?

Back 45

from 6-8

Front 46

__________ __________ compete with the substrate for the same active site, occupying the active site thus preventing the substrates from binding

Back 46

competitive inhibitors

Front 47

________ ___________ bind to the enzyme in a location other than the active site, changing the shape of the enzyme and making it unable to bind to the substrate

Back 47

noncompetitive inhibitor

Front 48

What are allosteric sites

Back 48

Site on an enzyme at which most noncompetitive inhibitors bind

--sites serve as an on/off switch

Front 49

Role of allosteric activator

Back 49

binds to allosteric sites to keep an enzyme in its active configuration, thereby increasing enzyme activity.

Front 50

What is a coenzyme

Back 50

a non-protein organic molecule acting as an enzyme co factor

Front 51

What are some examples of coenzymes?

Back 51

Vitamin B6 and 12

2. modified nucleotides

Front 52

Which cofactor is employed by the enzyme carboxypeptidase?

Back 52

Zinc

Front 53

Carbohydrates and fats posses many of which bons

Back 53

C-H and C-O

Front 54

What does it mean for a reaction to be dehydrogenations?

Back 54

Chemical reaction involving the loss of a hydrogen atom. This is an oxidation that combine loss of an electron with loss of a proton

Front 55

What is NAD+?

Back 55

Nicotinamide adenosine dinucleotide- A molecule that becomes reduced (to NADH) as it carries high energy electrons form oxidized molecules and delivers the to ATP-producing pathways in the cell

Front 56

a vascular plant consist of a _______ system and a ________system

Back 56

root; shoot

Front 57

Where are leaves initiated?

Back 57

At the nodes of the shoot

Front 58

__________ ___________ can remain dormant, grow to form lateral branches or make flowers

Back 58

axillary buds

Front 59

Which system evolved 1st; roots or shoots

Back 59

shoots

-roots evolved later as an adaptation to living on land

Front 60

What is the function of the root system

Back 60

anchors plat and penetrates soil from which it absorbs water and ions crusial for the plants nutrition

Front 61

What is the function of the shoot system?

Back 61

consists of the stems and their leaves. Stems serve as a scaffold for positioning the leaves, the principal sites of photosynthesis

Front 62

The repeating unit of the vegetative shoot consists of

Back 62

the internode, node, leaf, and axillary bud, but not reproductive structures.

Front 63

How are plant cell types distinguisged

Back 63

by the size of their vacuoles, whether they are living or not at maturity, and by the thickness of their cellulose cell walls, a distinguishing feature of plant cell

Front 64

What is the protoplast of a cell and its function

Back 64

Protoplasts are cells which have had their cell wall removed, usually by digestion with enzymes. Cellulase enzymes digest the cellulose in plant cell walls while pectinase enzymes break down the pectin holding cells together.

Front 65

What are the molecules that make up the cell wall

Back 65

Cellulose, lignin and pectin

Front 66

What is cellulose

Back 66

a glucose polymer that is produced at the cellulose-forming rosettes in the cell membrane to form the cell wall. Cellulose fibers are laid down parallel to microtubules inside the cell membrane.

Front 67

What are the 3 types of tissue found in roots, shoots and leaves?

Back 67

1. Ground

2. Dermal

3. Vascular

Front 68

What is the function of ground tissue in plants?

Back 68

cells function in storage, photosynthesis, and secretion, in addition to forming fibers that support and protect plants.

Front 69

What is the function of vascular tissue in plants?

Back 69

conducts fluids and dissolved substances throughout the plant body.

Front 70

What is the function of dermal tissue in plants?

Back 70

primarily epidermis, is one cell layer thick in most plants, and it forms an outer protective covering for the plant.

Front 71

Where can the meristems be found?

Back 71

In root and shoot apices mostly

Front 72

What are meristem cells?

Back 72

Meristem cells are undifferentiated cells that can divide indefinitely and give rise to many types of differentiated cells.

----clusters of small cells with dense cytoplasm and proportionately large nuclei

----one cell divides to give rise to two cells, of which one remains meristematic, while the other undergoes differentiation and contributes to the plant body

Front 73

What is shared by meristem and animal stem cells?

Back 73

The retinoblastoma gene, which determines whether a cell continues dividing or differentiates

Front 74

What makes up the primary plant body?

Back 74

The primary plant body comprises the young, soft shoots and roots of a tree or shrub, or the entire plant body in some plants.

Front 75

What is the stoma?

Back 75

the space between two guard cells that regulates the size of the opening.

Front 76

What is the tmm mutation in Arabidopsis

Back 76

Too many mouths-mutation disrupts the normal pattern of cell division that spatially separates the stomata

Front 77

What does the TMM gene encode?

Back 77

a membrane-bound receptor that is part of a signaling pathway controlling asymmetrical cell division.

---- investigations of this and other stomatal patterning genes revealed a coordinated network of cell–cell communication that informs cells of their position relative to other cells and determines cell fate.

Front 78

What gene is repsonsible to trichome development?

Back 78

GLABROUS3 (GL3) -When trichome-initiating proteins, like GL3, reach a threshold level compared with trichome-inhibiting proteins, an epidermal cell becomes a trichome. Signals from this trichome cell now prevent neighbor cells from expressing trichome-promoting genes