Science Quiz "4.2"

____ are the organelles where photosynthesis takes place.

Chloroplasts

ATP and NADPH are the reactants of the light reactions.

False

organelle of photosynthesis

chloroplast

Why is water "split" during the light reactions?

to produce - 2 electrons - an atom of oxygen - 2 hydrogen ions

_____ turns of the Calvin cycle produce one molecule of _____.

two, glucose

During the light reactions, ____ & ____ are produced

ATP & NADPH

How is ATP made during the light reactions?

ATP synthase uses the energy to add a phosphate group to a molecule of ADP, which produces a molecule of ATP.

What is an electron transport chain? What is its role during these light reactions?

An electron transport chain is a series of electron-transport molecules. To capture energy & use it to pump more hydrogen ions into the thylakoid interior space.

In which steps of the light reactions is sunlight absorbed?

Step 1 & 4

A chemiosmotic gradient causes hydrogen ions to flow across the thylakoid membrane into the stroma.

True

During the Calvin Cycle, NADPH and ATP are used to make glucose.

True

Earth's oxygen comes from photosynthesis.

True

Electron transport occurs in the thylakoid membranes.

True

Light is absorbed by photostat end in the thylakoid membranes of chloroplasts.

True

Photons of sunlight can excite and energize electrons.

True

Photosynthesis provides almost all of the energy used by living things on Earth.

True

The Calvin cycle takes place in the stroma surrounding the thylakoid membranes of the chloroplast.

True

chlorophyll

a green pigment

Essentially, the oxygen we breathe is

a waste prod ur for photosynthesis

Making food with chemical energy instead of sunlight is called ____ .

chemosynthesis

process in which chemical energy, instead of sunlight, is used to make "food"

chemosynthesis

The green pigment, ____, absorbs light to start photosynthesis.

chlorophyll

series of electron-transport molecules, which pass electrons from molecule to molecule

electron transport chain

During the first stage of photosynthesis, two _____ are passed from molecule to molecule down the electron - transport chain.

electrons

During the Calvin cycle, ______ is produced.

glucose

main product of photosynthesis

glucose

By the end of the light reactions, energy from sunlight

has been stored in chemical bonds of NADPH and ATP.

The Calvin cycle occurs

in the stroma surrounding the thylakoid membranes of the chloroplast

Stage 1 of photosynthesis is called the

light reaction / light dependent

stage of photosynthesis in which the energy from sunlight is stored in ATP and NADPH

light reactions

During the first stage of photosynthesis, a molecule of _____ gas is released.

oxygen

space outside the thylakoid membranes within the chloroplast

stroma

Chloroplasts contain ___ which are made out of sac-like membranes, known as ____ membranes

thylakoid

sac-like membranes that make up the grams within the chloroplast

thylakoid membrane

stage of photosynthesis in which glucose is made

Calvin cycle

Stage 2 of photosynthesis is called the

Calvin cycle / light independent / dark cycle

All cells have chloroplasts.

False

Both stages of photosynthesis need sunlight to proceed.

False

During the light reactions, water molecules are made.

False

In photosynthesis, the Calvin cycle comes before the light reactions.

False

Like photosynthesis, chemosynthesis also relies on sunlight.

False

Two turns of the Calvin cycle produce two molecules of glucose.

False

What happens during the light reactions?

Light is absorbed and transformed to chemical energy in the bonds of NADPH & ATP.

energy carrying molecule

NADPH

The correct sequence of events in the light reactions is

absorption of sunlight, splitting of water, electrons flow down the electron transport chain, ATP is made.

The Calvin cycle

all of the above

Most _____ make food using photosynthesis.

autotrophs

ATP Synthase is

both an enzyme that makes ATP and a channel protein, and helps hydrogen ions cross the thylakoid membrane.

How do bacteria that live deep below the ocean's surface make food?

by chemosyntheis

Most autotrophs make "food" through the process of

photosynthesis

groups of molecules where sunlight is absorbed during the light reactions

photosystem