BIO103 Chapters 6 & 7

first law of thermodynamics

Energy cannot be created or destroyed

second law of thermodynamics

whenever energy is changed from one form to another, there is always a "loss" of usable

energy. The unusable, dissipated energy is known as entropy.

substrate

reactants of an enzymatically catalyzed reaction

enzyme active site

Site of the enzyme surface where substrate molecules binds

enzyme-substrate complex

A temporary complex formed when an enzyme binds to its substrate molecule(s)

cellular respiration formula

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

(1 glucose + 6 oxygen --> 6 Carbon Dioxide + 6 Water)

Photosynthesis formula

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

(6 carbon dioxide + 6 water -> 1 glucose + 6 oxygen)

Energy

The ability to do work or cause change

Chemical Energy

the food we eat

Mechanical Energy

Energy possessed through motion or position

Potential energy

stored energy

Kinetic Energy

energy of motion

catabolism

breaking down molecules to release energy

anabolism

building up molecules to store energy

metabolic pathway

A series of chemical reactions that uses the product of the previous reaction as a reactant for the next reaction

metabolism

What you make (-) what you use

induced fit model

Change in the shape of an enzyme's active site that enhances the fit between the active site and its substrate(s)

degradation

substrate is broken down into smaller products

synthesis

the substrates are combined to produce a larger product

Enzyme

protein that lowers the activation energy of a reaction

Cofactor

a molecule (typically metal ions) required to activate an enzyme

coenzyme

an organic cofactor (usually vitamins)

Enzyme activity _______with substrate concentration due to _______________

increases; more frequent collisions between substrate molecules

Enzyme activity _______ with temperature.

increases

inhibitor

a substance that binds to an enzyme and decreases its activity

Competitive Inhibition

The substrate and the inhibitor are

both able to bind to the active site, and they compete with one

another

Noncompetitive Inhibition

the inhibitor binds at the allosteric site causing the active site to change shape, making it unable to bind to its substrate

oxidation

loss of an electron

reduction

gain of an electron

OIL RIG

oxidation is LOSS

reduction is GAIN

where living organisims oxidize glucose

mitochondria

photosynthesis

chemical process by which green plants use light energy to produce food

two reactants in photosynthesis

carbon dioxide and water

two products in photosynthesis

glucose and oxygen

all life on earth ultimately depends on ____ ____

solar energy

autotroph

an organism that can produce their own food

heterotroph

an organism that cannot produce its own food

photoautotroph

an organism that uses light energy to make its own food

main factors that effect rate of photosynthesis

1) limited light

2) light saturation

3) temperature

stomata

small openings in a leaf where CO2 enters

the part of a chloroplast that contains chlorophyll and other pigments that absorb solar energy

thylakoid membrane

stroma

aqueous portion of a chloroplast

grana

multiple stacks of thylakoids

the two stages of photosynthesis

light reactions and light independent reactions (aka calvin cycle)

what does the light reaction stage of photosynthesis produce

ATP and NADPH

part of a plant that captures light for photosynthesis

chlorophyll

antenna pigments

a specified organelle that collects light energy and transfers it efficiently to reaction centers

chlorophyll A is an example of an __ __

antenna pigment

Light reaction process

• Chlorophyll absorbs energy

• Energized electrons move down electron transport chain

• electron transport chain makes ATP out of ADP and NADPH out of NADP+

Calvin cycle reactions

• CO2, NADPH, and ATP synthesize carbohydrates

Pigments

chemicals that absorb certain wavelengths of light

absorption spectrum

graph showing the relative absorption of various colors

Carotenoids

accessory pigments that absorb violet-blue-green and reflect orange-yellow light

things a plant can do with the light energy it captures

fluorescence, resonance transfer, heat, photosynthesize

fluorescence

the photon of light energy is reemitted at a longer wavelength b/c some of the energy is lost as heat before reemission

resonance transfer

captured light energy is transferred to another chlorophyll molecule

redox reaction

reduction-oxidation

photosystem

a pigment complex that helps collect solar energy like an antenna

what water releases when it splits

oxygen, hydrogen ions, and electrons

what is produced at the end of the calvin cycle

G3P

what stage occurs FIRST in the photosynthesis process?

light-dependent reaction

what stage occurs SECOND in photosynthesis?

calvin cycle