photosynthesis quiz

do all living things need energy to survive

yes

what form of energy do living things consume

food

where does almost all energy on earth come from

the sun

where is chemical energy from

from bonds between organic molecules

what is potential energy

stored energy

what is kinetic/heat energy

energy of movement

what is an autotroph

Organisms that can produce their own food from the light energy of the sun (producers)

what is a heterotroph

Organisms that obtain energy by eating other organisms (consumers)

what is the chemical energy that all living things need

ATP

ATP vs ADP

* atp has 3 phosphate groups
* adp has 2 phosphate groups, can bond with more to store energy

what is a coupled reaction

when one reaction powers another reaction

why are coupled reactions important

they are needed to keep producing energy

what is an example of a coupled reaction

photosynthesis → cellular respiration

what is oxidation

when something loses an electron

what is reduction

when something gains an electron

what is photosynthesis

the process where energy from the sun is used  to make sugars and starches and provide food for the organisms

what organisms can do photosynthesis

plants, algae, some bacteria

what is the formula for photosynthesis

6CO2 + 6H2O + light energy → C6H12O6 + 6O2

what do plants release when water is split

oxygen gas (O2)

what does chlorophyll do

it absorbs sunlight for photosynthesis

what is chlorophyll a

a primary photosynthetic pigment that absorbs blue-violet and red-orange wavelengths

what is chlorophyll b

an accessory pigment that collects energy and passes it to Chlorophyll A. it absorbs blue and red wavelengths

why do plants appear green

chlorophyll doesn’t absorb green light and instead reflects it out, which makes the plants look green

what color light does chlorophyll b absorb the most of

blue

what color light does chlorophyll a absorb the most of

red

what is carotene

orange accessory pigment

what is anthocyanin

red, blue, or purple accessory pigment

why does anthocyanin have different colors

what color reflects is based on pH

what colour is chlorophyll a

blue-green

what colour is chlorophyll b

yellow green

what is Chromatography

separating pigments by using a solvent that allows for dissolution of the pigment at differing places based on its dissolving time

what is the Rf value of carotene

.95

what is the Rf value of xanthophyll

.71

what is the Rf value of chlorophyll a

.65

what is the Rf value of chlorophyll b

.45

what are the stomata and where are they found

they are openings that allow for gas exchange

in the leaves of the plant

what is the main function of chloroplasts and where are they found

their main function is photosynthesis

they are found in plant cells

where are chlorophylls found

in the chloroplasts

do chloroplasts have 1 or 2 membranes

2

is the outer membrane of chloroplasts smooth or folded

smooth

what is the thylakoid

the inner membrane of chlorophyll folded into disc-shaped sacs called thylakoids

what are the thylakoids connected by

stromal lamellae

what is in the thylakoids

chlorophyll and other accessory pigments

what is thylakoid lumen

narrow aqueous (watery) space within the thylakoid membrane

what is the stroma

fluid surrounding the grana inside the chloroplast

what are photosystems and where are they found

organized clusters of chlorophyll and other pigments

found in the thylakoid

what are stacks of thylakoids called

granum (singular), grana (plural)

where are the cells on a leaf that do photosynthesis

the middle layer of a leaf (palisade mesophyll)

what do the other cells on the leaves do

they store gasses and can make sugar (spongy mesophyll)

What is an electron carrier

A molecule capable of accepting one (or more) electrons from another molecule (electron donor), and then ferry these electrons to donate to another during the process of electron transport

ex: NADP+

What happens to NADp+ when chlorophyll captures energy

NADP+ accepts and holds 2 high-energy electrons that have moved through the proteins in the thylakoid membrane along with a hydrogen ion (H+). This converts the NADP+ into NADPH.

What does the NADPH do

carries high-energy electrons to chemical reactions elsewhere in the cell where they will be donated.

What is the conversion from NADP+ to NADPH an example of

it’s an example of one way some of the energy of sunlight can be trapped/captured in chemical form.

is NADP+ oxidized or reduced when it forms NADPH

reduced

what does photosystem II require

sunlight, water, adp

what does photosystem II produce

O- and 2 H+ when water is split and light energy produces ATP and NADP+

where does photosystem II occur

it occurs in the thylakoid membrane

What happens to to the H+s in PSII

One H+ enters PSII to replace the missing electron. The other H+ stays in the lumen of the thylakoid

What happens to the O- after it is split from h2o

it combines with others to form O2 gas

what does water split in PSII cause

causes a build-up of H+ in the membrane creating a high proton concentration gradient

what does the high proton concentration gradient lead to

it leads to high speed diffusion of the H+ through the ATP synthase in the membrane

the atp synthase creates ATP with the H+ in the concentration gradient

what happens to the built up H+

eventually make ATP (energy) and NADPH by traveling through the electron transport chain

what type of organic molecule is atp synthase

protein (enzyme)

What happens to the ATP and NADH after it goes through the electron transport chain

they move into the Calvin Cycle

What happens to electrons in PSII

Chlorophylls in PSII release electrons when a photon of light hits the chlorophylls. Photons excite the electrons. Excited electrons will then pop out of PSII and are grabbed by proteins in the thylakoid membrane called the cytochrome series. Each protein decreases the energy in that electron as it moves through them. This is an electron transport chain (ETC). Eventually, the electron moves down and is accepted into photosystem I.

is ATP production part of PSII or PSI

PSII

what is photolysis

splitting water

is the high proton gradient stable or unstable

unstable

does PSI happen before PSII

no, they can happen simultaneously in light dependent reactions

why is PSI called PSI and PSII called PSII

PSI was discovered first

what does PSI require

sunlight, electrons from PSII, NADP+

what does PSI produce

NADPH

where does PSI happen

thylakoid membrane

what does the NADPH produced from PSI do

NADPH provide the energy to build energy-containing sugars from low-energy compounds

what happens to the electron from PSII when it enters PSI

The PSI protein picks it up from the last cytochrome protein

how does PSI start

the NADP+ wants the electron from PSII

what happens to the NADP+ when it picks up electrons

it reduces and forms NADH and then moves to the light independent phase

what is the light independent reaction also called

calvin cycle

what light conditions can the calvin cycle happen in

it can happen in light and dark

what does the calvin cycle require

CO2, NADPH, and ATP

where does the calvin cycle happen

in the stroma outside the thylakoids

are the ATP and NADPH created in the light dependent reactions stable or unstable

unstable, they cannot store their energy for more than a few minutes

what happens during the calvin cycle

plants use the energy that ATP and NADPH contain to build glucose.

how many stages does the calvin cycle have

3

what are the stages of the calvin cycle

carbon fixation, reduction, regeneration

what is carbon fixation

changing CO2 into solid carbon by combining with a solid carbon molecule (RuBP).

why does CO2 need to be changed from a gaseous form to a solid form

living organisms cant use gaseous carbon

what enzyme joins CO2 with RuBP to make solid carbon compounds

Rubisco

how many carbons does RuBP have

5

what happens to the RuBP in carbon fixation

RuBP is transformed from a 5 to a 6-carbon molecule and then two 3-carbon molecules

What happens to the ATP during carbon fixation

ATP is oxidized to release energy to do this work. ADP + Pi return to ATP synthase.

what is the end product of carbon fixation

2 molecules of 3-PGA

what does reduction start with

the two 3-PGA made in fixation

what happens in reduction

NADPH is oxidized and donates electrons to reduce those two molecules of 3-PGA to form G3P

what molecule leaves the calvin cycle

1 molecule of 3-C G3P

how many turns of the calvin cycle does it take to make 1 glucose molecule

2

what molecule is needed to continue the calvin cycle

1 molecule of 3-C G3P

why is the regeneration stage of the calvin cycle necessary

because it is a cycle and we have used the components, we have to regenerate (recreate) RuBP

what happens to G3P and ATP in the regeneration stage

ATP is oxidized and G3P is reduced

what is needed to change G3P back to RuBP

ATP