Exam 2 (chapter 8, 16)

Question 1

A metabolic pathway is halted by the inhibitory binding of its end product to an enzyme that acts early in the pathway

Answer 1

Feedback Inhibition

Question 2

Alters an enzyme’s function by changing it’s shape

Answer 2

Noncompetitive Inhibitor

Question 3

Takes the place of a substrate in the active site

Answer 3

Competitive Inhibitor

Question 4

Addition of a phosphorus

Answer 4

Phosphorylation

Question 5

Some are organic ions (vitamins)

Answer 5

Coenzymes

Question 6

Some are inorganic ions (zinc, copper, iron)

Answer 6

Cofactors

Question 7

What denatures an enzyme?

Answer 7

Changes in salt concentration, temperature, and pH

Question 8

A very specific place on the enzyme where the reactants bind

Answer 8

Active Site

Question 9

• Lower activation energy
• Mostly proteins, highly specific for certain molecules
• Speed up reactions
• Do not affect energetic differences between reactants and products
• Not used up or altered by reaction
• Does not change the chemical relationship between reactants and products

Answer 9

Enzymes

Question 10

The energy required to initiate a reaction

Answer 10

Activation Energy

Question 11

Using the energy released in exergonic reactions to drive essential endergonic reactions

Answer 11

Energy Coupling

Question 12

Absorbs energy, products rich in potential energy

Answer 12

Endergonic Reactions

Question 13

Releases energy, products have less potential energy

Answer 13

Exergonic Reactions

Question 14

Beating of cilia and flagella, movement of an entire cell, contraction of muscle

Answer 14

Mechanical Work

Question 15

Moving substances “uphill” across a membrane, from low to high concentration

Answer 15

Transport Work

Question 16

Building of polymers to monomers

Answer 16

Chemical Work

Question 17

Stored energy (electrical gradient, energy stored in bonds)

Answer 17

Potential Energy

Question 18

Energy that is actually doing work, motion

Answer 18

Kinetic Energy

Question 19

The entropy (degree of disorder) is always increasing

• Energy is lost when it is transformed from one form to another
• Energy is generally lost as heat

Answer 19

Second Law of Thermodynamics

Question 20

The total amount of energy in the universe is constant

• Energy cannot be destroyed or created, it can only be changed from one form to another
• Energy from life comes from the sun (Plants convert light energy to chemical energy via photosynthesis)

Answer 20

First Law of Thermodynamics

Question 21

The capacity to do work

*All organisms required it to stay alive

Answer 21

Energy

Question 22

The total of all the chemical reactions that take place in a multicellular organism

Answer 22

Metabolism

Question 23

Showed that killed pathogenic bacteria could transfer virulence to non-pathogenic bacteria; This newly acquired trait of pathogenicity was inherited by all the descendants of the transformed bacteria

Answer 23

Frederick Griffith (1928)

Question 24

Identified the transforming substance as DNA

Answer 24

Avery, McCarty, MacLoed (1944)

Question 25

Concluded that DNA was injected by the phage must be the molecule carrying the genetic information that makes the cells produce new viral DNA and proteins *Provided powerful evidence that nucleic acids, rather than proteins, are the hereditary material, at least for certain viruses

Answer 25

Hershey and Chase (1952)

Question 26

Chargaff's Rules: A=T, C=G

Answer 26

Erwin Chargaff (1950)

Question 27

Made an x-ray diffraction photograph of DNA which showed the helical structure; Concluded that the sugar- phosphate backbone was on the outside, died in 1958

Answer 27

Rosalind Franklin (1953)

Question 28

- Determined base pairing - Determined that the two strands of DNA were involved-double helix - Determined that the strands ran in opposite directions-antiparallel

Answer 28

Watson and Crick

Question 29

2 rings

Answer 29

Purine

Question 30

1 ring

Answer 30

Pyrimidine

Question 31

The genetic information of the cell *Carries instructions for every protein *Carries regulatory sequences The order of the bases on a strand of DNA specifies the primary structure of all of the proteins the organism is capable of making *The instructions for one protein is carried by one gene (one gene, one polypeptide)

Answer 31

DNA

Question 32

The DNA strands separate, enzymes use each strand as a template to assemble the new strands

Answer 32

Template Model

Question 33

- Catalyze the addition of nucleotides on the 3' end of the growing chain of nucleotides (from 5' to 3' end) - If nucleotides pair incorrectly, it is removed and replication occurs

Answer 33

DNA Polymerase

Question 34

Synthesizes continuously, DNA replication occurs in the same direction as the replication fork

Answer 34

Leading Strands

Question 35

Has fragments going in the opposite direction

Answer 35

Lagging Strands

Question 36

Where split is occurring

Answer 36

Replication Fork

Question 37

The daughter strands are ?? to the parent molecule

Answer 37

Identical

Question 38

Breaks hydrogen bonds between complementary pairs (unzips DNA)

Answer 38

Helicase

Question 39

Adds a RNA primer to initiate replication

Answer 39

Primase

Question 40

Adds nucleotides after RNA primer

Answer 40

DNA Polymerase III

Question 41

Removes RNA primer

Answer 41

DNA Polymerase I

Question 42

Joins okazaki fragments

Answer 42

DNA Ligase

Question 43

Helps with the untwisting of DNA

Answer 43

Topoisomerase

Question 44

Binds to single strands to keep them from rejoining

Answer 44

Single Strand Binding Protein

Question 45

Cuts out bad DNA segments

Answer 45

Nuclease

Question 46

If a segment of DNA is able to replicate, it must include ??

Answer 46

at least one origin of replication