Biology Unit 3

Where does energy come from?

The sun

Energy must be converted from ________ to a form that organisms can use_________.

light energy, chemical energy

Photosynthesis-

the process in which organisms use energy from sunlight to make sugar (glucose)

Organisms that perform photosynthesis:

plants, some protists (algae), some bacteria (cyanobacteria)

Where does photosynthesis occur?

Chlorplast

chlorphyll-

a pigment that absorbs light

Thylakoid-

a coin shaped membrane that contains chlorophyll

Grana-

stacks of thylakoids

Stroma-

a fluid that surrounds thylakoids (like cytoplasm)

Photosynthesis Equation

sunlight+6CO2+6H2O=C6H12O6+6O2

reactants-

what is needed

products-

what is made

photo=

light

synthesize=

to make

stomata-

where leaves take in CO2 and release oxygen

chemosynthesis-

using chemicals for energy instead of sunlight (for organisms in dark environments)

light dependent reactions-

need light

light independent reactions-

does NOT need light

Where do light dependent reactions occur?

thylakoids

Where do light independent reactions occur?

stroma

What goes in during light dependent reactions?

sunlight & water

What comes out during light independent reactions?

CO2, ATP, and NADPH

What comes out during light dependent reactions?

Oxygen, ATP, and NADPH

What happens during light dependent reactions?

chlorophyll absorbs energy from sun, transfers to ATP and NADPH, water is split, and oxygen is released

What happens during light independent reactions?

CO2 and energy from light dependent reactions are used to make sugar

NADPH

Nicotinamide Adenine Dinucleotide Phosphate

Cellular Respiration is…

the main process in which cells convert glucose to ATP

ATP-

(adenosine triphosphate) the energy carrying molecules of cell “fuel”, energy stored in chemical bonds has to be broken to be released, rechargeable

Aerobic-

with oxygen (ex. exercise)

Anaerobic-

without oxygen

List organisms that do cellular respiration:

plants, animals, all other eukaryotes

Where does cellular respiration occur?

Mitochondria

Where does glycolysis occur?

Cytoplasm

During glycolysis, what goes in?

Glucose

During glycolysis, what comes out?

Electrons, 2 ATP molecules, pyruvate (broken down glucose)

What happens during glycolysis?

Glucose is broken down into 2 pieces that enter the Krebs cycle and a little ATP is made, Electrons go into ETC

Where does the Krebs cycle occur?

Mitochondria (Matrix)

During the Krebs Cycle, what goes in?

broken-down glucose

During the Krebs Cycle, what comes out?

2 ATP, electrons, CO2

What happens in the Krebs Cycle?

The rest of glucose is broken down and electrons that are extracted go to the ETC, a little ATP is made

Where does the electron transport chain occur?

Mitochondria (inner membrane)

During the Electron Transport Chain, what goes in?

Electrons from glucose & O2

During the Electron Transport Chain, what comes out?

28-34 ATP, Water

What happens in the Electron Transport Chain?

Energy is transformed to a chain of proteins in the inner membrane of mitochondrion, proteins use energy to pump hydrogen ions against the membrane, ATP created, water formed

Fermentation-

a process by which energy can be released from food molecules in the ABSENCE of oxygen

Who experiences lactic acid fermentation?

Animals & bacteria

Where does lactic acid fermentation occur?

Cytoplasm

During lactic acid fermentation, what goes in?

pyruvate & NADH

During lactic acid fermentation, what comes out?

2 ATP, 2 Lactic Acid

What happens during lactic acid fermentation?

Glycolysis, pyruvate broken down to lactic acid

What are foods lactic acid make?

yogurt, sauerkraut, kimchi, cheese

Who does alcoholic fermentation occur in?

Bacteria & yeast

Where does alcoholic fermentation occur?

Cytoplasm

During alcoholic fermentation, what goes in?

pyruvate & NADH

During alcoholic fermentation, what comes out?

CO2, 2 ATP, ethanol

What happens during alcoholic fermentation?

glycolysis, pyruvate broken down into ethanol

What are foods made by alcoholic fermentation?

bread, wine, beer

_______ respiration is more ________ than ________ respiration.

Aerobic (34 ATP), efficient, anaerobic (2 ATP)

ATP becomes ADP

released energy (bond broken)

ADP becomes ATP

stored energy (bond reformed)

When a phosphate group is removed…

ATP becomes ADP (adenosine diphosphate (di=2)