Biology Chapter 7 - Photosynthesis

Autotrophs

produce their own food by using photosynthesis (or chemosynthesis) to produce organic molecules from inorganic inputs.

heterotrophs

must consume other organisms to get their food.  Other organisms are the source of organic molecules.

auto

plants are ____trophs

grana, granum

stacked thylakoids =

chloroplast

photosynthesis occurs in _______ organelles

stroma

fluid surrounding thylakoids/granum =

pigment in thylakoid membrane that captures sunlight

chlorophyll

sunlight

A

H2O

B

light dependent reactions

C

Oxygen

D

thylakoid

E (the green ovals)

ATP

E (the little starbursty thing in the middle)

NADPH

F

CO2

G

Calvin cycle

H

Glucose

I

Stroma

Y

6CO2 + 6H2O → C6H12O6 + 6O2

Chemical equation for photosynthesis

allows for gas exchange (CO2 enters, oxygen exits)

stomata function

absorbs, reflects

Chlorophyll _____ __red, blue, violet wavelengths, and _______ green and yellow wavelengths.__

Chlorophyll reflects green

Why do leaves appear green?

sunlight

What energy powers photosynthesis?

substances (proteins) that absorb light, give color to objects based on which wavelengths they absorb or reflect.

What are pigments?

thylakoid membrane

Where is chlorophyll found?

reduced

CO2 is _______ to a G3P molecule

stroma

Where does the Calvin cycle occur?

thylakoid membrane

Where do the light dependent reactions occur?

light dependent reactions

energy-capturing reaction

calvin cycle

carbon dioxide becomes glucose in which reaction

do include other atoms

the carbon molecules in the calvin cycle do or do not include other atoms besides carbon?

light dependent reaction

NADP+ takes up energized electrons in which reaction

light dependent reaction

NADPH and ATP are made in which reaction

calvin cycle

NADPH and ATP are used in which reaction

oxygen and glucose

2 things released by photosynthesis

H2O, CO2, sunlight

3 things reacting in photosynthesis

ATP, NADPH, O2

3 products of LDR

ADP+P, NADP+, glucose

3 products of Calvin cycle

H2O, ADP+P, NADP+, sunlight

4 reactants of LDR

CO2, ATP, NADPH

3 reactants of Calvin cycle

blue

Photosynthesis happens most efficiently at ____ wavelengths

green

Photosynthesis happens least efficiently at ____ wavelengths

Calvin cycle and light dependent reactions

2 major sets of reactions involved in photosynthesis

chemiosmosis

Process by which hydrogen ions are concentrated in the thylakoid space

RuBP, Rubisco, G3P

CO2 is fixed to ______ __by__ _______, and is reduced to__ _____

one out of 6

How many G3P molecules leave the Calvin cycle each turn?

regenerating RuBP

the other five G3P cells are used for what?

5-carbon molecule in Calvin cycle

RuBP

enzyme that joins RuBP and CO2

Rubisco

they immediately split apart into two 3 carbon molecules

What happens when RuBP and CO2 join?

carbon fixation, reduction, regeneration of RuBP

3 stages of the Calvin cycle

CO2 joins to RuBP using rubisco

What happens in carbon fixation?

the 3-carbon molecule is reduced to G3P using atp and NADPH

What happens in reduction?

reduction and regeneration

In what stages of the calvin cycle is ATP used?

Electrons fuse to 3-carbon molecule using energy of ATP

What is the role of atp and nadph in reduction?

6

How many G3P are made in reduction?

G3P reforms RuBP to continue the cycle

What happens in regeneration?

glucose

G3P is used to create *_____*

C3

Most plants are ____ plants

C3

What type of plants photorespirate?

oxygen enters the plant, creating a useless product that must be broken down

photorespiration

stomata only open at night

CAM plant adaptation

fixation stage happens in a different cell from the rest of the Calvin cycle

C4 plant adaptation

CAM

succulents and cactus are ____ plants

capture sunlight energy and guide excited electrons to the electron transport chain

What is the function of photosystem II?

re-energize electrons to be sent to reduce NADP+

What is the function of photosystem I?

harvest energy from excited electrons to actively transport H+ ions across the thylakoid membrane to increase the concentration gradient

What is the function of the electron transport chain?

lower, higher

The concentration of H+ ions is ______ __in the stroma and__ _____ in the thylakoid space

H+ ions will then passively transport by facilitated diffusion through ATP synthase

What is the function of the concentration gradient of H+ ions in the thylakoid membrane/stroma?

ATP synthase spins like a water wheel, providing the energy to create ATP from ADP and P

What happens when the H+ ions flow through ATP synthase?

protons

H+ ions are also known as

water splits and provides electrons

How does photosystem II replace lost electrons?

H+ ions (protons), electrons, and oxygen

3 things released when water splits

lumen

thylakoid space is also known as

C3

carbon dioxide is fixed into a 3-carbon molecule in the fixation stage in _____ plants