Bio Review

Front 1

Integrin

Back 1

Connects the cytoskeleton of a cell to the extracellular matrix.

Front 2

Plasmodesmata

Back 2

Used for communication between plant cells

Front 3

Interior of Phospholipid Bilayer

Back 3

Hydrophobic; consists of fatty acid tails

Front 4

Transporter molecules vs transporter proteins

Back 4

All transporter molecules are transporter proteins, but not all transporter proteins are transporter molecules.

Front 5

What happens to an animal cell placed in a hypertonic solution

Back 5

Water will move out of the cell, and the cell will plasmolyze.

Front 6

Transporter Molecules

Back 6

Consist of protein arranged in alpha helices and beta pleats. Are not all identical.

Front 7

Antiporter

Back 7

A glucose transporter molecule that moves in both directions.

Front 8

Coupled Transport

Back 8

The simultaneous or sequential passive transfer of molecules or ions across the plasma membrane. Uses the concentration gradient established by active transport.

Front 9

Kinase

Back 9

An enzyme that adds a phosphate to a protein.

Front 10

Paracrine Signaling

Back 10

Characterized by ligands that are secreted by neighboring cells.

Front 11

Behavior of a hydrophilic ligand

Back 11

Can attach to a membrane receptor which, in turn, initiates a cellular response via one or more secondary messengers.

Front 12

Redundancy of glycogen to glucose pathway

Back 12

Two different ligands can use the same signaling pathway to bring about the formation of glucose from glycogen. Efficient from a biochemistry point of view because one pathway is used for normal glucose release and the other pathway is for emergency energy demands, such as during the “fight or flight” response.

Front 13

cAMP

Back 13

A secondary messenger in signal transduction.

Front 14

Insulin

Back 14

A ligand that signals the cell to turn glucose into glycogen. Received by the receptor tyrosine kinase.

Front 15

Effect of kinase cascades

Back 15

Cause amplified cellular response.

Front 16

IP3

Back 16

A secondary messenger. Once activated it opens calcium ion channels on the endoplasmic reticulum.

Front 17

Oncogenes

Back 17

Genes that can cause cancer when mutated.

Front 18

Behavior of hydrophobic ligands

Back 18

Have their receptors in the interior of the cell wall, and are able to pass through the phospholipid bilayer.

Front 19

Clathrins

Back 19

Responsible for receptor-mediated endocytosis.

Front 20

Channel Proteins

Back 20

Form pores and are involved in facilitated diffusion.

Front 21

Carrier Proteins

Back 21

Bind with the molecules being transported and use ATP for transport in some manner.

Front 22

Phenylalanine

Back 22

A hydrophobic, nonpolar amino acid that is a precursor for tyrosine. Would not be phosphorylated by a kinase.

Front 23

Receptor Tyrosine Kinases

Back 23

Unique because they involve the cross-phosphorylation of dimerized transmembrane molecules. Are cell-surface receptors that receive many growth factors, cytokines, and hormones.

Front 24

Gap Junctions

Back 24

Specialized inter-cellular connections in animals; connect cell cytoplasms directly to each other. The means by which rapid muscle cell communication occurs.

Front 25

Structure of ATP

Back 25

A ribose sugar, adenine, and three phosphate molecules.

Front 26

G-protein self-limitation

Back 26

Hydrolyze GTP to GDP, thereby inactivating themselves.

Front 27

G-protein pathway sequence

Back 27

Ligand > g-protein coupled receptor > g-protein > effector > second messenger > response protein > response.

Front 28

Entropy

Back 28

Unavailable, disorganized energy. Has a tendency to increase.

Front 29

Enthalpy

Back 29

The energy stored in chemical bonds.

Front 30

Redox reaction

Back 30

Oxidation and reduction occur simultaneously.The molecule that gains an electron has been reduced, and has a higher energy level.

Front 31

Caveat of energy conversions

Back 31

The conversion from one energy form to another never ends with all of the energy from the first form being converted to the next; some energy is always lost.

Front 32

Negative change in G

Back 32

The reactants have more energy than the products; this is called an exergonic reaction, and represents energy release.

Front 33

Enzymes

Back 33

Can be proteins or ribosomes. Lower energy of activation.

Front 34

Catalysts

Back 34

Not consumed by the the reactions they facilitate, nor do they change the proportions of the input or output.

Front 35

Polypeptides

Back 35

Consist of amino acids.

Front 36

Allosteric inhibition

Back 36

Inhibition through indirect means - a molecule binds to the allosteric site, warping the molecule shape.

Front 37

Energy of a bike ride

Back 37

The cyclist is using ATP to produce energy through an exergonic reaction. The energy in his energy bar began as an endergonic reaction in the Calvin Cycle.

Front 38

Reactions in biochemical pathways

Back 38

Use the product of one reaction as the substrate for the next reaction.

Front 39

Catabolic pathway

Back 39

Much less likely to be subject to feedback inhibition than an anabolic pathway because the end products of a catabolic pathway are lost as either heat from energy metabolism or as degraded end products and eliminated as waste, and therefore these products can’t feedback on initial enzymes in the pathway.

Front 40

Thylakoids

Back 40

The site of chlorophyll molecules, where the light dependent reactions occur.

Front 41

Oxygen in photosynthesis

Back 41

Derived from water.

Front 42

Effect of light striking a chlorophyll molecule

Back 42

The chlorophyll molecule becomes oxidized.

Front 43

Major absorption spectra for synthesis

Back 43

Occurs in red and blue regions.

Front 44

Flow of electrons in light reaction

Back 44

Electrons flow from H2O to NADPH.

Front 45

Photosystem Mechanism

Back 45

The electrons from Photosystem I are used to form NADPH, and these electrons are replaced from Photosystem II. The electrons in the latter case are replaced from water, which was split by a manganese-based enzyme attached to PSII. The electrons from PSII are used to create a hydrogen proton gradient, which is then used to produce ATP.

Front 46

Chemiosmosis

Back 46

Results in the production of ATP.

Front 47

Locations of photosystem I/ATP

Back 47

Photosystem I and ATP synthase are located on the stroma lamella so that the end products of energy are dumped directly into the stroma where the Calvin Cycle occurs.

Front 48

G3P

Back 48

Direct output of the Calvin cycle.

Front 49

Calvin Cycle

Back 49

Occurs in the stroma; represents an endergonic reaction. Its direct output is G3P.

Front 50

Photorespiration

Back 50

Occurs in hot and dry environments because the enzyme rubisco is sensitive to both CO2 and O2. When photorespiration does occur, the effect is to reverse carbon fixation.

Front 51

Photorespiration in C4 plants

Back 51

Counteracted by the enzyme phosphoenolpyruvate carboxylase, which operates in the mesophyll cells. This is a spatial solution.

Front 52

C4 versus CAM plants

Back 52

Both use C3 photosynthesis; however, C4 plants solve the photorespiration problem with a spatial solution, whereas the CAM plants solve it with a temporal solution.

Front 53

Role of oxygen gas in our cells

Back 53

To accept electrons from the ETC and produce H2O.

Front 54

Catabolism

Back 54

The metabolistic process of splitting larger molecules into smaller ones.

Front 55

Substrate phosphorylation

Back 55

When an enzyme is used to produce ATP directly.

Front 56

Anabolism

Back 56

The synthetic aspect of metabolism.

Front 57

Krebs Cycle

Back 57

For each molecule of pyruvate that enters, 3 molecules of CO3 are produced by ddecarboxylation, and in the process, the high energy molecule NADH is formed for each molecule of CO2 produced.

Front 58

In respiration, which molecule is formed first, water or carbon dioxide - and where is it produced?

Back 58

Carbon dioxide is formed first, in the Krebs cycle.

Front 59

Where does most of the energy stored in glucose show up?

Back 59

In oxidative phosphorylation, via aerobic respiration in mitochondria.

Front 60

Chemiosmosis results from...

Back 60

Electrons moving through the ETC, creating a proton gradient, and H+ moving through ATP synthase to produce ATP.

Front 61

Actual yield of ATP versus theoretical yield

Back 61

Smaller, because of the energy required to move NADH and pyruvate into the mitochondrial matrix.

Front 62

Thermogenesis

Back 62

Occurs when the H+ passes through a channel in the mitochondrial inner membrane created by an uncoupling protein into the mitochondrial matrix and produce heat rather than ATP.

Front 63

Beta-oxidation

Back 63

The process by which 2-carbon units of fatty acid chains are converted to Acetyl-Co A.

Front 64

Phosphofructokinase

Back 64

The control point for converting fructose 6-phosphate to fructose 1,6-biphosphate. Inhibited by high levels of ATP.

Front 65

Methanogens

Back 65

Use CO2 as a final electron acceptor (instead of oxygen) to produce CH4 (methane).

Front 66

Griffith's experiment

Back 66

Showed that genetic material could be transferred from dead to live bacteria.

Front 67

Friedrich Miescher

Back 67

Discovered DNA, and called it 'nuclein'.

Front 68

Chargaff

Back 68

Studied the composition of DNA from different sources, and found that the proportions of A equal that of T and G equals that of C.

Front 69

Phosphodiester bonds

Back 69

Hold nucleotides together

Front 70

Hydrogen bonds

Back 70

Hold together complementary strands of DNA (between the bases)

Front 71

Hershey-Chase experiment

Back 71

DNA from the parent bacteriophage appeared in progeny bacteriophage.

Front 72

Watson and Crick

Back 72

Interpreted DNA structure, but did zero primary research of their own.

Front 73

Direction of DNA synthesis

Back 73

5' to 3'

Front 74

Primase

Back 74

Tells DNA polymerase where to begin copying

Front 75

Replisome

Back 75

Composed of a primosome and 2 DNA Pol III enzymes

Front 76

DNA Pol I

Back 76

Removes primers and fills gaps.

Front 77

DNA Pol III

Back 77

The major enzyme that synthesizes DNA.

Front 78

Ligase

Back 78

Joins the DNA segments.

Front 79

Okazaki fragments

Back 79

Found in the lagging strand.

Front 80

Leading vs lagging strand synthesis

Back 80

Both the physical structure of DNA and the action of polymerase enzyme is different on the lagging strand.

Front 81

Telomeres

Back 81

Protect the ends of DNA strands.

Front 82

Complementary strand

Back 82

Consists of the complementary base pairs to the primary strand

Front 83

Replication of eukaryote DNA

Back 83

non-linear

Front 84

Neurospora experiments

Back 84

Provided evidence that genes specify enzymes.

Front 85

Central Dogma Theory

Back 85

DNA to RNA to protein. Does not hold true for ALL protein synthesis.

Front 86

Codon

Back 86

Consists of three bases and specifies a single amino acid.

Front 87

Universality of genetic code

Back 87

Except for a few minor exceptions, the genetic code is universal.

Front 88

Why is there no proofing with respect to RNA polymerase and the formation of RNA?

Back 88

RNA is short-lived, therefore errors do not accumulate or exist for any length of time.

Front 89

Alternative gene splicing

Back 89

Explains how the human genome contains 25,000 genes but can encode over 80,000 different mRNAs.

Front 90

tRNA

Back 90

A bifunctional molecule; transfers a specific active amino acid to a growing polypeptide chain at the ribosomal site of protein synthesis during translation.

Front 91

Peptidyl transferase

Back 91

An enzyme that couples the NH3 group from the amino acid in SIte A to the carboxyl group on the amino acid in site P in rRNA and polypeptide sequencing.

Front 92

Ef-Tu

Back 92

Responsible for bringing tRNA to mRNA and making sure the codons are correctly paired; is the only known example of validation in an RNA system.

Front 93

Gene

Back 93

A concept that defies simple explanation; expresses a phenotype, codes for enzymes...

Front 94

Anti-codons in tRNA

Back 94

The same as the complimentary strand in DNA, except T is replaced by U.

Front 95

Rough endoplasmic reticulum (RER)

Back 95

"Rough" because of the association of the membrane with rRNA. Associated with the RER by signal recognition particles.

Front 96

Prokaryote reproduction

Back 96

Reproduce asexually by binary fission, and do not require assembly or disassembly of a nuclear membrane.

Front 97

Nucleosome

Back 97

A complex of DNA plus histone proteins composed of arginine and lysine.

Front 98

FtsZ

Back 98

A protein in prokaryotes that shows a high degree of similarity to tubulin; assists in binary fission.

Front 99

Cohesin

Back 99

Holds chromatids together

Front 100

Chromatids

Back 100

Held together by cohesin, and become independent chromosomes in anaphase.

Front 101

Congression

Back 101

In prometaphase, when the chromosomes end up with their centromeres all situated in middle of the spindle, at a site known as the metaphase plate. An essential prerequisite for orderly separation. At this point, homologous pairing is not important.

Front 102

Epidermal growth factor

Back 102

Found in saliva; is responsible for stimulating certain cells to divide by overriding mitotic control mechanisms.

Front 103

p53

Back 103

A proteint hat plays a key role at the G1/S checkpoint. Its role is to monitor DNA integrity. If there are problems, p53 apoptosis. If p53 is damaged, uncontrolled cell division usually results.

Front 104

Nucleolus

Back 104

The part of the nucleus in which rRNA synthesis occurs, which produce proteins (enzymes). One of the last structures to leave and one of the first structures to form during mitosis.