Igcse Biology Syllabus

Front 1

Classification

Back 1

Chapter 1

Front 2

Movement

Back 2

An action by an organism or part of an organism causing a change of position pr place.

Front 3

Respiration

Back 3

The chemical reactions in cells that break down nutrient molecules and release energy for metabolism.

Front 4

Sensitivity

Back 4

The ability to detect or sense stimuli in the internal and external environment and to make appropriate responses.

Front 5

Growth

Back 5

A permanent increase in size and dry mass by an increase in cell number or cell size or both.

Front 6

Excretion

Back 6

Removal from organism of the waste products of metabolism (chemical reaction in cells including respiration.

Front 7

Nutrition

Back 7

Nutrition is the taking in of nutrients for energy, growth and development; Plants requite light, carbon dioxide, water and ions; animals need organic compounds and ions and usually water.

Front 8

Role of Classification Systems

Back 8

Aims to reflect evolutionary relationships.

Front 9

What is Classification based on?

Back 9

Traditionally based on morphology and anatomy.

Front 10

Morphology

Back 10

The overall form and shape of their bodies.

Front 11

Anatomy

Back 11

The detailed body structure which could be determined by dissection.

Front 12

Species

Back 12

A group of organisms that can reproduce and produce fertile offspring.

Front 13

Binomial System

Back 13

An internationally agreed system in which the scientific name of an organism is made up of two parts showing the Genus and Species.

Front 14

More accurate way of Classification

Back 14

The sequence of bases in DNA () and of Amino Acids in proteins used.

Front 15

Features in cells of a living organism

Back 15

1. Cytoplasm

2. Cell Membrane

3. DNA

4. Ribosomes

5. Enzymes

Front 16

Cytoplasm

Back 16

Jelly-like material that is found in cells.

Front 17

Cell Membrane

Back 17

A very thin layer of fat and protein that surrounds every living cells.

Front 18

DNA (Deoxyribonucleic Acid)

Back 18

The chemical from which genes and chromosomes are made.

Front 19

RNA (Ribonucleic Acid)

Back 19

Its principal role is to act as a messenger carrying instructions from DNA for controlling the synthesis of proteins.

Front 20

Ribosomes

Back 20

Tiny organelles (a structure within a cell) where protein synthesis takes place.

Front 21

Enzymes

Back 21

Proteins that function as biological catalysts.

Front 22

Catalyst

Back 22

A substance that speeds up a chemical reaction and is not changed by the reaction.

Front 23

The main features used to place organisms into groups within the plant kingdom

Back 23

Kingdom

Phylum

Class

Orders

Family

Genus

Species

Front 24

Features of a virus

Back 24

A piece of DNA (Deoxyribonucleic Acid) or RNA (Ribonucleic Acid) surrounded by a protein coat.

Front 25

List main groups of vertebrates

Back 25

Mammals (e.g. Cat)

Birds (e.g. Parrot)

Reptiles (e.g. Lizard)

Amphibians (e.g. Frog)

Fish (e.g.Yellow Tale)

Front 26

Main groups of arthropods

Back 26

Myriapods

Insects

Arachnids

Crustaceans

Front 27

Cells:

Back 27

Chapter Two

Front 28

Cytoplasm of all cells contain

Back 28

Many dissolved substance, especially proteins. Metabolic reactions takes place there.

Front 29

What occurs in the Mitochondria?

Back 29

Aerobic respiration

Front 30

Mitochondria

Back 30

Organelles in which aerobic respiration takes place, releasing energy for use by cells.

Front 31

Organelle

Back 31

A structure within a cell.

Front 32

Magnification and size of biological specimens

Back 32

Magnification = size of drawing / length of real object

OR length in drawing / length of real spider

OR size of real object = size of drawing x magnification

Front 33

Tissue

Back 33

A group of cells with similar structures, working together to perform a shared function.

Front 34

Organ

Back 34

A structure made up of a group of tissues, working together to perform specific functions.

Front 35

Organ System

Back 35

A group of organs with related functions, working together to perform body functions.

Front 36

The Definition and Function of a Cell Membrane

Back 36

Thin layer of protein and fat. Partially permeable which lets some substances through but not others.

Front 37

The Definition and Function of a Cell Wall

Back 37

(Plant cells only) Made of cellulose. Helps to protect and support the cell.

Front 38

The Definition and Function of a Cytoplasm

Back 38

Clear jelly, nearly all water. Substances dissolved in it, metabolic reactions take place.

Front 39

The Definition and Function of a Vacule

Back 39

Space within the Cytoplasm of a cell, enclosed by a Membrane and typically containing a solution of sugars and other substances, called Cell Sap.

Front 40

The Definition and Function of a Chloroplast

Back 40

(plant cells only) Contains chlorophyll, which absorbs energy from sunlight and makes food via photosynthesis.

Front 41

The Definition and Function of a Nucleus

Back 41

Is where genetic information is stored. Helps cell make the right proteins. Info kept in chromosomes which are made up of DNA.

Front 42

Cilliated Cells are responsible for

Back 42

movement of mucus in the trachea and bronchi

Front 43

Root Hair Cells are responsible for

Back 43

The absorption of moisture and nutrients from the soil.

Front 44

Xylem Cells are responsible for

Back 44

Conduction and support and consists of several different types of cells: fibers for support, parenchyma for storage, and tracheary elements for the transport of water.

Front 45

Palisade Mesophyll Cells are responsible for

Back 45

Photosynthesis.

Front 46

Nerve Cells are responsible for

Back 46

Conduction of Impulses.

Front 47

Red Blood Cellsare responsible for

Back 47

The transport of Oxygen

Front 48

Sperm and Egg Cellsare responsible for

Back 48

Reproduction

Front 49

Example of a Tissue

Back 49

The layer of muscle in the stomach wall.

Front 50

Example of an Organ

Back 50

The Stomach.

Front 51

Example of an Organ System

Back 51

Digestive System - Mouth, Intestines, Stomach,

Front 52

Fact -

Back 52

All cells, except prokaryotes (a microscopic single-celled organism which has neither a distinct nucleus with a membrane nor other specialized organelles) have a mitochondria and rough endoplasmic reticulum.

Front 53

Fact -

Back 53

Cells with high rates if metabolism (like muscle cells) requires a large number of mitochondria to provide sufficient energy.

Front 54

Fact -

Back 54

Energy for diffusion comes from the kinetic energy of random movement of molecules and ions.

Front 55

Movement in and out of Cells:

Back 55

Chapter 3

Front 56

Diffusion

Back 56

The net movement of molecules from a region of their higher concentration to a region of their lower concentration down a concentration gradient, as a result of their random movement.

Front 57

Factors that Influence Diffusion

Back 57

Surface Area

Temperature (The higher the temperature, the faster the atoms, molecules and ions move)

Concentration Gradients (Molecules spread out from a higher concentration to an are of lower concerntration)

Distance

Front 58

Where does the energy come from for Diffusion?

Back 58

It comes from the Kinetic energy, caused by the random movement of molecules and ions.

Front 59

Osmosis

Back 59

The net movement of water molecules from a region of higher water potential (dilute solution) to a region of lower water potential (concentrated solution), through a partially permeable membrane.

Front 60

The importance of diffusion of gases and solutes

Back 60

Living organisms obtain many of their requirements by diffusion. They also get rid of many of their waste products in this way.

Front 61

How do substances move through the Cell Membrane

Back 61

Substances move into and out of cells by diffusion through the Cell Membrane.

Front 62

The importance of water potential and osmosis in the uptake of water by a plant

Back 62

Plants gain water through osmosis in their roots from the soil. Without a water potential gradient, water will be lost from the roots.

Front 63

Turgor Pressure

Back 63

Turgor pressure pushes the plasma membrane against the cell wall of plant, bacteria

Front 64

How are plants supported by the Turgor Pressure?

Back 64

The plant cell is tight and firm by the pressure of the water pressing against the walls, keeping the plant upright.

Front 65

The importance of Active Transport as a process for movement across membranes

Back 65

Cells need to take in substances which are only present in small quantities around them. Often concentration of root hair cells are higher than soil, but despite that the root hair cells are still able to take in nitrate ions via Active Transport.

Front 66

Active Transpoort

Back 66

The movement of molecules and ions in or out of a cell through the cell membrane, from a region of their lower concentration to a region of their higher concentration against a concentration gradient, using energy released during respiration.

Front 67

How do protein molecules move particles across a membrane during active transport

Back 67

1. Glucose molecules enters the transport proteins.

2. Transport protein changes shape. The energy is provided by respiration.

3. Changes of shape of transport protein pushes glucose molecules into the cell.

Front 68

Glucose

Back 68

A simple sugar which is an important energy source in living organisms and is a component of many carbohydrates.

Front 69

Fact -

Back 69

Water diffuses through a partially permeable membrane via Osmosis.

Front 70

what is the process of water moving in and out of cells through the cell membrane?

Back 70

Water moves in and out of cells by Osmosis through the cell membrane.

Front 71

Fact -

Back 71

Plants are supported by the pressure of water inside the cells pressing outwards on the cell wall.

Front 72

The Chemicals of Life

Back 72

Chapter 4

Front 73

What elements are Carbohydrates made of?

Back 73

Carbon (C) + Hydrogen (H) + Oxygen (O)

Front 74

The smaller molecules that make up Carbohydrates are

Back 74

Simple sugars (monosacharides)

Front 75

Polysaccharides

Back 75

A carbohydrate (e.g. starch(plant), cellulose (plant), or glycogen(animal cells)) whose molecules consist of a number of simple sugar molecules join together.

Front 76

Is sugar soluble or insoluble?

Back 76

Soluble

Front 77

Are polysaccharides soluble or insoluble?

Back 77

Insoluble

Front 78

Why do organisms need Carbohydrates?

Back 78

Easily available energy (17kj/g0

Front 79

Testing for Carbohydrates - Reducing Sugars

Back 79

Add Benedict's Solution to food and heat it - if the food contains a reducing sugar, a brick-red color will be produced.

Front 80

Testing for Carbohydrates - Starch

Back 80

Simply add Iodine solution to a sample of food - if food contains starch a blue-black color i obtained.

Front 81

What elements are Fats (also known as Lipids) made of?

Back 81

Carbon (C) + Hydrogen (H) + Oxygen (O)

Front 82

The smaller molecules that make up Fats are

Back 82

Fatty acids and glycerol

Front 83

Are fats soluble or insoluble?

Back 83

Fats are insoluble in water.

Front 84

Why do organisms need Fats?

Back 84

Storage of energy (39kj/g);

Insultion;

making cell membranes.

Front 85

What are Fats called in liquid form?

Back 85

Fats that are liquid are called oils.

Front 86

Testing for Fats and Oils

Back 86

Chop food and shake it up with ethanol -

Pour the ethanol into water -

If fat i present, the fat-ethanol mixture should break up into millions of tiny droplet and would turn white and opaque, like milk. -

If no fat is present the mixture of water and ethanol should remain transparent.

Front 87

What elements is Protein made of?

Back 87

Carbon (C) + Hydrogen (H) + Oxygen (O) + Nitrogen (N)

Front 88

The smaller molecules that make up Protein are called

Back 88

Amino acids

Front 89

The different sequences of Amino Acids

Back 89

There are 20 kinds of amino acids.

They can be joined together to make a protein molecule. For most protein molecules, their shape directly affects their function. The shape of the enzyme determines which reactions the can catalyse.

Front 90

Is Protein soluble or insoluble?

Back 90

Some are soluble and some are insoluble.

Front 91

Why do organisms need Protein?

Back 91

They need it to produce/make cells, antibodies, enzymes, haemoglobin; also used for energy.

Front 92

Testing for Protein

Back 92

The Biuret Test:

Mix food in water -

Add dilute copper sulfate solution -

Dilute potassium hydroxide solution is gently added -

A purple color indicates that protein is present, if protein is not present the solution will remain blue.

Front 93

The Structures of DNA

Back 93

Two strands coiled together to form a double helix.

Each strand contains chemicals called bases.

Cross-links between the strands are formed by pairs of bases.

Front 94

The roles of water as a solvent in organisms

Back 94

needed for chemical reaction. Needed for transport, for example - plasma contains water so that substances like glucose can dissolve in it and get transported around the body. Also needed to get rid of waste products.

Front 95

DCPIP (chemical compund) test for Vitamin C

Back 95

Measure DCPIP into test tube -

Add lemon juice toDCPIP -

Count how many drops are needed beforeDCPIP loses its blue color.

Front 96

Enzymes

Back 96

Chapter 5

Front 97

Catalyst

Back 97

A substance that increases the rate of a chemical reaction and is not charged by the reaction.

Front 98

Enzymes

Back 98

Proteins that function as biological catalysts.

Front 99

Why are enzymes important in all living organisms?

Back 99

Without enzymes, the reactions would take place very slowly or not at all. Enzymes ensure that the rates of metabolic action are great enough to sustain life.

Front 100

Enzyme Action (with reference to complementary shape)

Back 100

Enzymes work by allowing the molecule of the substance on which it is acting to fit into. The fit has to be perfect. The enzyme is like a lock, into which another molecule fits into like a key.

Front 101

Substrate

Back 101

The substance which is present at the beginning of the reaction.

Front 102

Product

Back 102

The substance which is made by the enzyme reaction.

Front 103

The Properties of Enzymes (6)

Back 103

All enzymes are ___P(1)___. Enzymes are made ___I(2)___ by ___H(3)___ temperatures. Because they are ___P_M(4)___. Enzymes work best at a ___P(5)___ temperature. Which is ___(6)___ degrees Celsius. Enzymes also work best at a particular ___(7)___ level. Enzymes are ___C(8)___. This means that each kind of ___E(9)___ will only ___C(10)___ one kind of ____C_R(11)____.

Front 104

Answers

All enzymes are 1. Proteins. Enzymes are made 2. Inactive by 3. High temperatures. Because they are 4. Protein Molecules. Enzymes work best at a 5. Particular temperature. Which is 6. About 37 degrees Celsius. Enzymes also work best at a particular 7. pH level. Enzymes are 8. Catalysts. This means that each kind of 9. Enzyme will only 10. Catalyse one kind of 11. Chemical Reaction.

Back 104

1. Proteins

2. Inactive

3. High

4. Protein Molecules

5. Particular

6. About 37 degrees Celsius

7. pH

8. Catalysts

9. Enzyme

10. Catalyse

11. Chemical Reaction

Front 105

Effect of changes in Temperatures

Back 105

Most chemical reactions happen faster at higher temperatures. Enzymes can be damaged by high temperature (40 degrees Celsius upwards). The enzyme loses shape and becomes denatured. Its optimum temperature is 37 degrees Celsius.

Front 106

Effect of changes in pH

Back 106

pH of a solution affects the shape of an enzyme. Most enzymes are their correct shape at a pH of 7. If pH becomes very acidic or alkaline, they denature.

Front 107

Definition of Denatured (in terms of Enzymes)

Back 107

Is when an enzymes molecules has changed its shape so much that the substrate cant fit into it.

Front 108

Plant Nutrition

Back 108

Chapter 6

Front 109

Definition of Photosynthesis

Back 109

The process by which plants manufacture carbohydrates from raw materials using energy from light.

Front 110

Word equation for Photosynthesis

Back 110

carbon dioxide + water ----> Sunlight / chlorophyll <---- glucose + oxygen

Front 111

Balanced Chemical equation for Photosynthesis

Back 111

6CO2 + 6H2O ----> Sunlight / chlorophyll <---- C6H12O2 + 6O2

Front 112

Necessity for chlorophyll, light and CO2 (Carbon Dioxide) for Photosynthesis

Back 112

Chlorophyll traps sunlight energy to be used in photosynthesis reaction. (light energy is trapped and absorbed, then the molecule is released, making CO2 combine with water. The glucose that is made contains energy that was not originally in the sunlight. In this process, light energy is tranferred to chemical energy.

Front 113

Chlorophyll

Back 113

A green, light-absorbing pigment found inside chloroplasts in plant cells.