Biology test 3

Energy

Energy

the capacity of a cell to do work

Energy Cycle

Plants absorb light energy and convert it to chemical energy

Types of energy

Chemical, Light, Heat, Wind, Electrical , Nuclear

Potential Energy

Stored energy, glucose (C6H12O6) Capacity to do work

Kinetic

Used Energy, Energy of Motion

Food Molecules

Chemical bonds are potential energy, Glucose, Carbohydrates, Lipids, Proteins

Oxidation-Reduction

transfers energy

Redox Reaction

energy transfers in organisms, electron transport chains

Heat Energy in cells

Cells are too small to maintain a significant internal temperature

Heat Measurement

1 joule = .239 calories, kilocalories

Thermodynamics

the study of energy and its transformations

Transformation

No energy is being made or destroyed

Entropy

heat speeds up molecules creating disorder

Metabolism

the sum of all chemical reactions in a cell, makes energy available for cellular processes, putting together or breaking down

Heterotroph

consume food to produce energy

Autotrophs

photosynthesis to produce energy

Anabolic reactions

Building molecules, linking of amino acids to form proteins

Catabolic reactions

breaking down molecules, degradation of starch to monosaccharides

Delta G

Free energy left at the end of a reaction

Exergonic Reaction

Catabolic, Delta G<0, Spontaneous

Endergonic Reaction

Anabolic, Delta G>0

ATP

energy currency of cells, not stored well in cells (negative charges repel each other)

Enzymes

speed up reaction by lowering the activation energy, most are proteins

Activation Energy

energy needed to destabilize chemical bonds

Substrate

reactant which binds to enzyme

Product

end result or reaction

Active site

enzymes catalytic site, substrate fits into active site

Conezyme or Cofactor

assists the substrate in making the active site whole, vitamin

Co factor

metals, iron zinc

Enzyme optimal conditions

heat (98.6), pH

feedback inhibition

turn off the first enzyme in a metabolic pathway

Competitive Feedback inhibition

Active site become blocked off

Non-competitive (Allosteric) Feedback inhibition

molecule bonds to an enzyme and changes the shape of the active site

ATP losing a phosphate

ADP

Chemical Equation for Cellular Respiration

C6H12O6 + 6O2 -> 6CO2 + 6H2O + ATP

1 Glucose

36-38 ATP

Stages of ATP

23 steps to inhibit combustion in cells, Heat is given off

Molecular cars to move electrons

FADH, NADH2

Dehydrogenations

strip hydrogen of protons and electrons

Electron Carriers

Soluble, membrane-bound

Two ways to Make ATP

Enzymes, Electron Transport

Substrate Level Phosphorylation

Adding a phosphate, Ancient, used in Glycolysis

oxidative phosphorylation

need oxygen to add phosphate

Simple organisms

re-attach phosphate with an enzyme

4 Steps of Cell respiration

Glycolysis, Pyruvate Oxidation to Acetyl CO-a, Krebs Cycle, Electron Transport

Glycolysis (fermentation)

Occurs in cytoplasm 12 Steps No oxygen Main products - 2 ATP, 2 Pyruvates (3 Carbons), 2 NADH Yeast, Human Muscle cells

Pyruvate Oxidation to Acetyl Co-a

Occurs in the double membrane of the mitochondria Produces 2 Acetyle CO-a, 2 NADH, 2 CO2

Krebs Cycle (Citric Acid)

Occurs in the Matrix Turns twice for 1 Molecule of glucose Makes carries - 8 NADH, 2 FADH Acetyle Co-a -> Oxaloacetate Makes 2 ATP, 4 CO2 9 Reactions

Electron Transport (Chemiosmosis)

Occurs in Cristae ATP synthesis pump NADH and FADH can carry 2 electrons Concentration gradient of H+ 32-34 ATP

Aerobic respiration

Controlled by feedback inhibition Phosphofructokinase controls glycolysis

Deamination of Proteins

breaking into amino acids

Beta oxidation of Fats

fats are broken down into fatty acids and glycerol

Anaerobic respiration

Some living organism thrive NO Oxygen present Use inorganic molecules such as sulfur, nitrate, C02 or metals to transpire Archaea

Fermentation in Yeast

2 ATP, 2 Pyruvate (3Carbon), 2 NADH (enzymes) Uses ATP Reuse NADH Breaks Pyruvate into CO2 and Ethanol

Fermentation in Human Muscle Cells

2 ATP, 2 Pyruvate (3Carbon), 2 NADH (enzymes) Uses ATP Reuses NADH Breaks Pyruvate into Lactic acid

Photosynthesis

6 CO2 + 6 H2O + Light -> C6H12O6 + 6O2 Endergonic Takes place in chloroplast

Light Dependent Reaction

Splitting water and harvesting hydrogens Occurs in thylakoid Light energy is captured by chlorophyll Electrons come from H20 Endergonic

Calvin Cycle (Light Independent Reaction)

ATP is used to dismantle CO2 and put carbon into glucose Occurs in Stroma 6x = 1 Molecule of Glucose Ribisco

Jan Baptista van Helmont (1577-1644)

Where do plants get nutrients, Tree experiment

Joseph Priestly (1733-1804)

There is something in the air, mouse and candle experiment

Jan Ingenhouz (1730-1799)

Plants produce oxygen, Discoverer of photosynthesis

Jean Senebier (1742-1809)

Plants need CO2

Julius Mayer (1830-1895)

Plants transform energy

Julius von Sachs (1832-1897)

Starch is produced by light

FF Blackman (1866-1947)

Photosynthesis is a multistep process and one requires light

Cornelius Van niel (1897-1985)

Photosynthesis is a light dependent redox reaction

Melvin Calvin (1911-1997)

Traces the chemical path that carbon follow to form Glucose

Where does photosynthesis take place?

Leaves

Mesophyll

Chloroplasts located

Stomata

allows gases to diffuse in and out, controlled by guard cells

Grana

A stack of thylakoids

Stroma

Location of synthesis reaction

Photons

highly energized packets of light, kinetic light energy

Electromagnetic Spectrum

Differentiates light based on its wavelength Visible range is the wavelength we can see Radiowaves, Infrared, UV light, Xrays, Gamma Rays

Plant Pigments

Capture the light energy

Chlorophyll A

main pigment to absorb light

Chlorophyll B

helps chlorophyll A

Carotenoids

Yellow and Orange

Anti oxidants

Beta Carotenes and other carotenoids neutralize free radicals

B Carotene

Vitamin A precursor

Why do leaves change color

Heat wave, Shorter Days

Photosystem 1 & 2

Enzymes with Antenna that Captures light, chlorophyll is located here

Rubisco

enzyme that bonds to CO2 in photosynthesis

G3P (PGAL)

sugar, product of calvin cycle

RUBP

CO2 binds in Calvin Cycle

Photorespiration

Closing of stomata, Build up of oxygen in the plant, no CO2 to make sugar

C3 Photosynthesis

Main photosynthesis, occurs in mesophyll

C4 Photosynthesis

Occurs in the bundle sheath cell, CO2 -> Malate, ex. sugarcane, corn

CAM photosynthesis

Stomata only open at night, CO2 -> Malate, ex. tropical fruits, cactus

Pepsin

Stomach enzyme, Acid, PH-2, Breaks down food

Trypsin

Enzyme in large intestine, Basic, PH-11, Absorbs nutrients

Final electron acceptor in cell respiration

Oxygen

Final electron acceptor in yeast

Acetaldehyde

Final electron acceptor in human muscle cells

Pyruvate

Visible Light

380-700 nanometers, chlorophyll will absorb blue and red, Green is reflected

Anoxygenic Photosynthesis

Does not produce Oxygen, Found in Purple bacteria, green sulfur bacteria, green non sulfur bacteria, heliobacteria

Oxygenic Photosynthesis

Produces oxygen, Found in cynobacteria, algae, all land plants

Ultraviolet radiation

Shortest wavelengths, high energy photons, causes sunburn and skin cancer

Infrared Radiation

longer wavelengths, converted immediately to heat

Absorption spectrum

the range and efficiency of photons it is capable of absorbing