What is the structure of a chloroplast?

A chloroplast is bounded by a double envelope and contains a fluid stroma in which flat membranous thylakoids are stacked into grana; it also holds circular DNA, 70S ribosomes and often starch grains.

What is the function of a chloroplast?

It is the site of photosynthesis, with the chlorophyll in the thylakoid membranes trapping light energy that is used in the stroma to make carbohydrate from carbon dioxide and water.

In what two ways is a palisade mesophyll cell adapted for photosynthesis?

It is packed with chloroplasts that can be moved within the cytoplasm towards the light, and it is elongated and arranged vertically near the upper surface of the leaf so that light passes through as few cell walls as possible.

What is contained in the large central vacuole of a plant cell?

It contains cell sap, a solution of water with sugars, amino acids, mineral ions, organic acids and sometimes pigments and waste products.

State two functions of the large permanent vacuole in a plant cell.

It stores water, ions and other solutes, and by filling with water it pushes the cytoplasm against the cell wall to create the turgor that supports the cell.

OCR A-Level Biology B H422

The Developing Cell: Cell Division and Cell Differentiation

Topic overview The cell cycle and mitosis Apoptosis in growth and repair Stem cells and cell differentiation

The Developing Individual: Meiosis, Growth and Development

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Cells and Microscopy

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Water and Its Importance in Plants and Animals

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Nucleic Acids

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Patterns of Inheritance

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Population Genetics and Epigenetics

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Pathogenic Microorganisms

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Photosynthesis, Food Production and Management of the Environment

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Plant Reproduction

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The Nervous System and the Identification and Consequences of Damage

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The Effect of Ageing on the Nervous System

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The Heart and Monitoring Heart Function

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Transport Systems in Mammals

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Gas Exchange in Mammals and Plants

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Transport Systems in Plants

Topic overview The need for transport systems in plants Vascular tissue in roots, stems and leaves Water uptake and movement through the plant Transpiration and Its Measurement Translocation in the Phloem

Cells and Microscopy

Plant and prokaryotic cells

3 things to know
Components 01, 02 and 03

Overview

Recall questions on the structure and function of chloroplasts, palisade mesophyll cells, the vacuole, cell sap and tonoplast, the cellulose cell wall, and prokaryotic cells with their nucleoid, plasmids, mesosomes, pili and flagella, and how they differ from eukaryotic cells.

What you need to know

Answer each one before you reveal it.

Your recallNot started

Key term

What is the tonoplast and what does it do?

Key term

Name three structures found in a plant cell but not in an animal cell.

Key term

What is a mesosome?

Questions from this subtopic

Each one with the model answer underneath.

1
What is the structure of a chloroplast?
Model answer
A chloroplast is bounded by a double envelope and contains a fluid stroma in which flat membranous thylakoids are stacked into grana; it also holds circular DNA, 70S ribosomes and often starch grains.
2
What is the function of a chloroplast?
Model answer
It is the site of photosynthesis, with the chlorophyll in the thylakoid membranes trapping light energy that is used in the stroma to make carbohydrate from carbon dioxide and water.
3
In what two ways is a palisade mesophyll cell adapted for photosynthesis?
Model answer
It is packed with chloroplasts that can be moved within the cytoplasm towards the light, and it is elongated and arranged vertically near the upper surface of the leaf so that light passes through as few cell walls as possible.
4
What is contained in the large central vacuole of a plant cell?
Model answer
It contains cell sap, a solution of water with sugars, amino acids, mineral ions, organic acids and sometimes pigments and waste products.
5
State two functions of the large permanent vacuole in a plant cell.
Model answer
It stores water, ions and other solutes, and by filling with water it pushes the cytoplasm against the cell wall to create the turgor that supports the cell.
6
What is the tonoplast and what does it do?
Model answer
The tonoplast is the partially permeable membrane surrounding the vacuole, and it controls which substances pass between the cell sap and the cytoplasm.

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The Developing Cell: Cell Division and Cell Differentiation

The Developing Individual: Meiosis, Growth and Development

The Development of Species: Evolution and Classification

Cells and Microscopy

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measles and .

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