Unit 3 - Metabolism

definition of metabolism

totality of chemical processes that occur within a cell to maintain life

enzymes are…

a globular protein, biological catalyst

enzymes speed up the rate of reaction by …

lowering activation energy needed

substrates bind to the enzyme’s ___

active site

enzyme specificity means…

shape of active site being complementary to specific substrate

the lock and key model is:

when enzymes are highly specified for one substrate

the induced fit model is…

when enzymes undergo conformational change to fit the substrate

factors that affect rate of reaction:

temperature, concentration

factors that affect enzyme activity:

temperature, substrate concentration, ph, enzyme levels

enzyme saturation occurs when…

substrate concentration is too high, all enzymes used up

enzymes occur in low concentrations in cells because they can be…

reused

what do cells need energy for?

metabolism (anabolism), active transport, movement

anabolism is

forming larger molecules from simpler molecules

catabolism is

breaking down larger molecules into simpler molecules

adenosine triphosphate is

immediate energy source

how is energy from atp produced?

the energy that holds the negative phosphates together is released (hydrolysis)

adenosine diphosphate is

uncharged battery form of atp

cellular respiration is…

release of energy from breaking down organic molecules

cellular respiration converts the energy in ___ into ATD+Pi

covalent bonds holding organic molecules together

describe anaerobic respiration:

• no oxygen

• small ATP yield (2)

• occurs in cytosol

what are the byproducts of anaerobic respiration?

• lactic acid (animals)

• ethanol + CO2 (plants)

describe aerobic respiration

• presence of oxygen

• high ATP yield (30)

  • occurs in mitochondria

what are the byproducts of aerobic respiration?

carbon dioxide + water

what is glycolysis (brief)

breaks down one glucose into two pyruvates and atp

mitochondrion’s inner membrane is folded into __ to maximize SA:V

cristae

rate of respiration can be measured by:

consumption of input (glucose/oxygen) or formation of product (carbon dioxide), or mass of plant

factors that affect respiration specifically

glucose concentration, oxygen availability

definition of photosynthesis

synthesizing simpler molecules from inorganic molecules using sunlight

what is the chemical equation of photosynthesis?

carbon dioxide + water (light+chlorophyll) = glucose, oxygen, water

the electrons in pigments…

absorb light at specific wavelengths and become energized

atp is produced in photosynthesis by:

harnessing the energy in pigment’s electrons

how does chromatography work?

pigments dissolved in fluid then passed through static material. pigments travel at different speed, so it separates

how to calculate Rf value? (identify the pigment)

distance pigment traveled / distance solvent traveled

chlorophyll absorbs which two pigments the best, and reflects which one

absorbs: red and blue. reflects: green

at which wavelength is photosynthesis happening the most?

400 nm and 700 nm

what is the range of useless wavelength for photosynthesis?

550nm to 650 nm

absorption spectra is …

amount of light absorbed by pigments

action spectra is …

rate of photosynthesis at a given wavelength

where does photosynthesis occur in plants

chloroplast

where does the light dependent reaction occur?

thylakoids

describe light dependent reaction

1. light is absorbed by pigments

2. energized electrons turn energy into ATP

3. Light energy breaks down water into oxygen and hydrogen (photolysis)

what is the waste product of light dependent reaction?

oxygen gas, exits through stomata

describe light independent reaction

1. uses hydrogen ions (from photolysis) and carbon dioxide to make glucose

2. catalyzed by Rubisco enzyme and uses the ATP to form covalent bonds

where does light independent reaction occur?

stroma

measuring photosynthesis methods:

1. measuring pressure change ( oxygen production )

2. pH change (carbon dioxide uptake —> creates acidic solution)

   1. mass change (biomass due to glucose production)

outline the carbon enrichment experiments

• predicting future plant growth as CO2 increase

  • using enclosed greenhouse gases and free air carbon dioxide enrichment