What is energy?

1
What is energy?

• Ability to do work

2
What are oxidation-reduction reactions?

• Chemical reactions in which there is a transfer
  of electron(s) from one reactant to another.
  Molecules receiving an electron are reduced and
  those donating an electron are oxidized.

3
What are the Laws of Thermodynamics?

• 1st Law energy can not be created nor destroyed
  it can only be converted and when it is
  heat is given off
• 2nd Law disorder in the universe is a continual
  process. Entropy

4
What is free energy?

• The energy available to do work in a system G
  is the symbol for free energy

5
What is activation energy?

• The amount of energy needed to help start a
  chemical reaction. Enzymes help to lower the
  activation energy required.

6
What are enzymes?

• Biological catalysts that help to lower
  activation energy and speed up chemical
  reactions.

7
How does temperature, pH, inhibitors, activators,
and coenzymes affect enzymatic activity?

• Temperature can render an enzyme inactive. Too
  hot denatures enzyme too flexible. Too cold
  enzyme is too rigid and can not flex around
  substrate.
• pH can dissociate the ions and cause an enzyme to
  degrade rendering it inactive.
• Inhibitors competitive blocks active site.
  Non-competitive (allosteric) distant site
• Activators speed up enzymes
• Coenzymes non-organic cofactors that help
  transfer electrons during a chemical reaction

8
What is ATP?

• Adenosine tri-phosphate is a high energy
  molecule used to help power biological systems.
  ATP has two high energy bonds (7.3 kcal)

9
What is a biochemical pathway?

• A serious of sequential steps involving more than
  one enzyme acting on the substrate and resulting
  in a final product which can release a by-product
  that has an affect on the first enzyme in the
  chain and can shut down the pathway feedback
  inhibition.

10
When an atom or molecule gains one or more
electrons, it is said to bereduced
11
Reactions that do NOT proceed spontaneously
because they require energy from an outside
source are calledendergonic
12
In an enzyme catalyzed reaction, the reactant
(being acted upon) is called thesubstrate
13
Enzymes are very specific in their choices of
substrates, because each different enzyme has an
active site thatis shaped to fit a certain
substrate molecule
14
ATP gives up energy when it is converted to ADP
phosphate
15
Enzymeslower the activation energy of a
reaction
16
In an endergonic reaction, the reactants
contain less free energy than the products
17
The energy available to do work in a system is
calledfree energy
18
What is cellular respiration?

• Converting the energy found in food molecules
  into ATP. The mitochondria are the site for
  aerobic respiration and the cytoplasm is usually
  where anaerobic respiration occurs.

19
How do electron acceptors play a role in cellular
respiration?

• They help to transfer high energy electrons from
  one system to another resulting in a complex
  biochemical pathway

20
What is NAD?

• Nicotidamide Adenine Dinucleotide is a co-factor
  or co-enzyme that helps transfer the energy in
  electrons from one system to another

21
What is glycolysis?

• The breakdown of glucose into two molecules of
  pyruvic acid (pyruvate)

22
What is the Krebs Cycle?

• Described by Hans Krebs, the Citric Acid Cycle or
  KrebsCycle is a cycle of chemical reactions
  converting organic molecules into different forms
  all the while producing high energy cofactors
  such as NADH and FADH2 and ATP

23
What is the Electron Transport Chain?

• Specialize proton pumps (cytochrome proteins)
  embedded in the mitochondrial membrane are
  powered by the products of the Krebs Cycle to
  pump hydrogen ions across the membrane into the
  outer compartment of the mitochondria. They flow
  back across through a special protein enzyme (ATP
  synthase) and oxidatively phosphorylate ADP into
  ATP

24
What is chemiosmosis?
25
What is fermentation?
26
Fermentation can be described as takes place in
the absence of oxygenrecipient of hydrogen atoms
is organic moleculeswater is not a
by-productdoes NOT involve the Krebs cycle all
of the above
27
A common process to all living organisms, aerobic
and anaerobic isglycolysisfermentationKrebs
cycleElectron transport chain
28
The decarboxylation of pyruvate produces
NADHAcetyl CoACo2ATPOnly a, b, c are
correct
29
The coenzyme electron carriers produced in the
Krebs cycle arePyruvate and acetyl CoAFADH and
NADHNAD and NADH
30
The oxygen used in cellular respiration
ultimately ends up asH2O
31
Muscle cells, when anaerobic, producelactate
32
What substance is produced by the oxidation of
pyruvate and feeds the Krebs cycle?acetyl CoA
33
What role does oxygen play in oxidative
respiration?final electron acceptor in the
electron transport chain
34
During the electron transport chain, H are
pumped out of the cellout of the mitochondrial
matrix into the outer compartment of the
mitochondria
35
ATP is a molecule containing energy in its
phosphate bonds. (7.3 kcal).
36
Because the chemical formation of ATP is driven
by a diffusion force similar to osmosis, this
process is referred to as chemiosmosis
37
In the absence of oxygen, hydrogen atoms
generated by glycolysis are donated to organic
molecules in a process called fermentation
38
What are the reactants and products of
photosynthesis?

• Reactants are carbon dioxide and water
• Products are sugar, oxygen, and metabolic water

39
How is light captured by green plants?

• Wavelengths of light called photons are absorbed
  by specific pigments in the leaf. The most
  abundant is chlorophyll accessory pigments
  called carentenoids and xanthophylls absorb what
  chlorophyll can not and channel the energy to the
  chlorophyll

40
What is visible light?

• That part of the electromagnetic spectrum that we
  see as white light, which is a blend of all the
  colors of the rainbow

41
What determines whether an element/compound can
absorb/reflect light waves (photons)?

• The outermost electrons (valence) of a pigment
  molecule determines what wavelength will be
  absorbed

42
Know what happens during photosystem I II.

• Water is split by sunlight and the energy
  (electron) powers two sets of photosystems that
  eventually produce ATP and NADPH which will be
  used in the stroma of the chloroplast for the
  light independent reactions

43
Understand the basics behind the Calvin Cycle.

• The Calvin cycle, described by Melvin Calvin is
  otherwise known as the dark reactions of
  photosynthesis or the light independent
  reactions. It is where carbon from carbon
  dioxide of animals is fixed into various organic
  molecules in a cycle that eventually produces
  sugar as the product.

44
What type of plants use the C4 pathway and why?

• Tropical plants that grow very fast have adopted
  this more efficient way to fix carbon into sugar.
  They are able to store excess carbon in bundle
  sheaths to be used during the dark reactions.

45
What type of plants use the Crassulacean Acid
Pathway (CAM)?

• Desert plants must use this form of making sugars
  because the live in hot arid environments. They
  must open their stomata at night when its cooler
  to take in carbon dioxide so that they do not
  dessicate.

46
What is the cell cycle?

• The lifecycle of a typical cell which involves
  interphase, mitosis, and cytokinesis. Interphase
  has three phases, G1, S, and G2.

47
What are the phases of the cell cycle?

• Interphase, Mitosis, and cytokinesis

48
What are somatic cells?

• Body cells which have a 2N number of chromosomes

49
What cellular division results in an exact copy
of DNA in the daughter cells?

• mitosis

50
What cellular division results in half the number
of chromosomes?

• meiosis

51
What are the phases of both mitosis and meiosis?

• Prophase, metaphase, anaphase, and telophase

52
What is crossing over?

• Exchanging of genetic material between homologous
  chromosomes during Metaphase I of meiosis

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