activate 2 biology

Addiction:

A need to keep taking a drug in order to feel normal.

Alcoholic:

A person who is addicted to alcohol.

Anus:

Muscular ring through which feces pass out of the body.

balanced diet:

Eating food containing the right nutrients in the correct amounts.

Bile:

Substance that breaks fat into small droplets.

Carbohydrase:

Enzyme that breaks down carbohydrates into sugar molecules.

Carbohydrate:

Nutrient that provides energy.

Catalyst:

Substance that speeds up a reaction without being used up.

Deficiency:

A lack of minerals, that causes poor growth

Depressant:

A drug that slows down the body's reactions by slowing down the nervous system.

Digestion:

Process where large molecules are broken down into small molecules.

digestive system:

Group of organs that work together to break down food.

Drug:

Chemical substance that affects the way your body works.

Enzyme:

Special protein that can break large molecules into small molecules.

Ethanol:

The drug found in alcoholic drinks.

Fibre:

Provides bulk to food to keep it moving through the digestive system.

food test:

Chemical test to detect the presence of particular nutrients in a food.

Gullet:

Tube that food travels down into the stomach.

Hypothesis:

An idea that is a way of explaining scientists' observations.

large intestine:

Organ where water passes back into the body, leaving a solid waste of undigested food called feces.

Lipase:

Enzyme that breaks down lipids into fatty acids and glycerol.

Lipids:

Nutrients that provide a store of energy and insulate the body.

Malnourishment:

Eating the wrong amount or the wrong types of food.

medicinal drug:

Drug that has a medical benefit to your health.

Mineral:

Essential nutrient needed in small amounts to keep you healthy.

Nutrient:

Essential substance that your body needs to survive, provided by food.

Obese:

Extremely overweight.

passive smoking:

Breathing in other people's smoke.

Protease:

Enzyme that breaks down proteins into amino acids.

Protein:

Nutrient used for growth and repair.

recreational drug:

Drug that is taken for enjoyment.

Rectum:

Feces are stored here, before being passed out of the body.

small intestine:

Organ where small digested molecules are absorbed into the bloodstream.

Starvation:

Extreme case of not eating enough food.

Stimulant:

A drug that speeds up the body's reactions by speeding up the nervous system.

Stomach:

Organ where food is churned with digestive juices and acids.

unit of alcohol:

10 ml of pure alcohol.

Villi:

Tiny projections in the small intestine wall that increase the area of absorption.

Vitamin:

Essential nutrients needed in small amounts to keep you healthy.

withdrawal symptom:

Unpleasant symptom a person with a drug addiction suffers from when they stop taking the drug.

Adaptation:

Characteristic that helps an organism to survive in its environment.

Chromosome:

Long strand of DNA, which contains many genes.

Competition:

Competing with other organisms for resources.

continuous variation:

Characteristic that can take any value within a range of values.

discontinuous variation:

Characteristic that can only be a certain value.

DNA:

Chemical that contains all the information needed to make an organism.

Evolution:

Development of a species over time

Extinct:

When no more individuals of a species are left anywhere in the world.

Fossil:

The remains of plants and animals that have turned to stone.

Gene:

Section of DNA that contains the information for a characteristic.

gene bank:

A store of genetic samples, used for research and to try to prevent extinction.

Interdependence:

The way in which living organisms depend on each other to survive, grow, and reproduce.

natural selection:

Process by which the organisms with the characteristics that are most suited to the environment survive and reproduce, passing on their genes.

Species:

Organisms that have lots of characteristics in common, and can mate to produce fertile offspring.

Variation:

Differences in characteristics within a species.

aerobic respiration:

Chemical reaction where glucose reacts with oxygen to release energy, carbon dioxide, and water.

Algae:

Green unicellular or multicellular organisms that perform photosynthesis and live underwater.

anaerobic respiration:

Chemical reaction that takes place without oxygen. Glucose is converted into lactic acid and energy is released.

Bioaccumulation:

The build up of toxic chemicals inside organisms in a food chain.

Chemosynthesis:

Reaction performed by bacteria, using energy transferred from chemical reactions to produce glucose.

Chlorophyll:

Green pigment that absorbs light for use in photosynthesis.

co-exist:

Plants and animals living in the same habitat at the same time.

Community:

The collection of the different types of organism present in an ecosystem.

Consumer:

Organisms that eat other organisms as food.

Deficiency:

A lack of minerals, that causes poor growth.

Ecosystem:

The name given to the interaction between plants, animals, and their habitat in a particular location.

Fermentation:

Chemical reaction used by microorganisms to convert glucose into ethanol, carbon dioxide, and energy.

Fertiliser:

Chemical containing minerals, normally applied to soil.

food chain:

A diagram that shows the transfer of energy between organisms.

food web:

A diagram showing a set of linked food chains.

Habitat:

The area in which an organism lives.

Haemoglobin:

The substance in blood that carries oxygen around the body.

Interdependence:

The way in which living organisms depend on each other to survive, grow, and reproduce.

Magnesium:

A mineral needed by plants for making chlorophyll.

Niche:

A particular place or role that an organism has in an ecosystem.

Nitrates:

Minerals containing nitrogen for healthy growth.

oxygen debt:

Extra oxygen required after anaerobic respiration to break down lactic acid.

Phosphates:

Minerals containing phosphorus for healthy roots.

Photosynthesis:

The process plants use to make their own food, glucose. In photosynthesis, carbon dioxide and water react together to make glucose and oxygen.

Plasma:

The liquid part of blood, which carries carbon dioxide to the lungs where it is exhaled.

Population:

The number of plants or animals of the same type that live in the same area.

Potassium:

A mineral needed by plants for healthy leaves and flowers.

Predator:

An animal that eats other animals.

Prey:

An animal that is eaten by another animal

Producer:

Organism that makes its own food using photosynthesis.

Stomata:

Holes found on the bottom of the leaf that allow gases to diffuse in and out of the leaf.