Chloroplast Structure

What is the function of chloroplasts?

Site of photosynthesis

Where are chloroplasts mainly found in plants?

Mesophyll cells of leaves

What is the main roles of chloroplasts?

Absorb light energy to convert it into chemical energy

What surrounds a chloroplast?

A double membrane

What are thylakoids?

Flattened sacs containing photosynthetic pigments in their membranes

What are grana?

Stacks of thylakoids

What are lamellae?

Membranous extensions connecting thylakoids

What is the stroma?

Fluid surrounding the thylakoids where the light independent reaction occurs

What is the function of starch grains in chloroplasts?

Store sugars

What is the function of chloroplast ribosomes?

Protein synthesis

What is the function of chloroplast DNA?

Codes for proteins involved in photosynthesis

Where are photosynthetic pigments found?

In thylakoid membranes

What is chlorophyll a?

The main photosynthetic pigment

Which wavelengths does chlorophyll a mainly absorb?

Red and blue light

Why do most plants appear green?

Chlorophyll reflects green light

What is chlorophyll b?

An accessory photosynthetic pigment

What is the function of chlorophyll b?

Broadens the range of light absorbed

What are carotenoids and xanthophylls?

Accessory pigments that absorb different wavelengths from chlorophyll

What is a photosystem?

A cluster of photosynthetic pigments in a thylakoid membrane

What are the two parts of a photosystem?

Light harvesting system and reaction centre

What pigments are found in the light harvesting system?

Chlorophyll a chlorophyll b and carotenoids

What is found in the reaction centre?

Two chlorophyll a molecules

What is the function of the light harvesting system?

Absorbs light energy and transfers it to the reaction centre

What is the function of the reaction centre?

Emits high energy electrons

Where are photosystems located?

Thylakoid membranes

What is chromatography used for in photosynthesis?

Separating and identifying photosynthetic pigments

Why do pigments separate during chromatography?

They travel different distances up the chromatography paper

What does an Rf value show?

The relative distance travelled by a pigment

What is the formula for Rf?

Distance travelled by pigment ÷ distance travelled by solvent

Why can Rf values identify pigments?

Each pigment has a characteristic Rf value