BIOLOGY NEW UNIT 1 2 3

Niche

The role an organism has in an ecosystem.

Habitat

The place where an organism lives.

Abiotic

A physical factor that affects an ecosystem, such as temperature or light intensity, ph, soil moisture

Community

All the living organisms of all species in an ecosystem.

Population

All the organisms of one species in an ecosystem.

Biodiversity

The number and abundance of species in an area.

Biotic

Describes living factors in the environment.

Producer

Organism that makes its own food. Green plants are producers.

Consumer

An organism which eats other organisms.

Pyramid of Numbers

A diagram that shows the number of organisms at each stage of a food chain.

Pyramid of Energy

A diagram that shows the energy content of the organisms at each stage of a food chain. This always takes the form of a pyramid.

Food Chain

the transfer of food energy between organisms in an ecosystem. from producer to primary to secondary consumer

Nitrate

Chemical absorbed by plant roots and used to make amino acids

Pitfall Trap

Apparatus used to sample small invertebrates in the soil by seeing which crawling animals have fallen in, must check frequently

Adaptation

Inherited characteristic that increases an organism's chance of survival

Mutation

A random change in the genetic information if happens during cell division then can be inherited if other than no

Natural Selection

The process whereby organisms better adapted to their environment tend to survive and produce more offspring.

Species

A group of organisms which can breed together to form fertile offspring.

Speciation

The formation of new species from an existing species. processes - isolation by barrier, mutation occur, due to selection pressures different phenotypes will be chosen, natural selection makes more offspring with the mutation and groups may become so different that if they come together again cant interbreed and produce fertile offspring and so are now separate species

Isolation

When a population is divided into two by a barrier which stops the sub-populations from breeding together

Selective Pressure

Something that makes it harder for an organism to survive in an environment.

Algal Bloom

Large growth of algae on the surface of water caused by the leaching of fertiliser. Dead algae form food for bacteria, so bacteria numbers increase. Bacteria use up oxygen, meaning less oxygen for other organisms

Fertiliser

Chemical added to the soil to improve crop yield. Often includes nitrates.

Indicator Species

A group of organisms which by their presence or absence indicate environmental quality

Biological Control

Natural control of pests using predators or parasites.

Interspecific competition

Competition for resources that are in short supply between members of different species this includes stuff like light, territory, food, shelter

Intraspecific competition

Competition for resources that are in short supply between members of the same species. more intense since they have the exact same needs and wants ie- light, territory, food, shelter and breeding partners

Quadrat

A square frame used for sampling plants in field work.

Omnivore

A consumer that eats both plants and animals

Light meter

A device to measure light intensity. Care must be taken not to shade the probe with the body

Moisture meter

Instrument used to measure level of moisture in the soil. Care must be taken to wipe the probe dry between readings

Paired Statement Key

A method of identifying organisms by answering a series of questions

Photosynthesis

Process by which plants use light energy to convert water and carbon dioxide into oxygen and sugar

Light Reactions

First stage of photosynthesis. Light energy trapped by chloro converted into chem energy, is used to split water into oxygen and hydrogen. Some energy is converted into the chemical ATP

Chlorophyll

Green pigment in plants that TRAPs light energy used to carry out photosynthesis

Carbon Fixation

the atp from the first stage is used to break down into energy to combine the hydrogen with the carbon to make sugar. this is an enzyme controlled reaction

Photosynthesis word equation

carbon dioxide + water \---sunlight/chlorophyll\---\> sugar + oxygen

Starch

A storage carbohydrate found in plants

Cellulose

A structural carbohydrate used to make plant cell walls

Limiting Factors of Photosynthesis

A factor which holds up the rate of photosynthesis because it is in short supply. May be light intensity, carbon dioxide concentration or temperature

Pesticide

Chemical which kills pests which can reduce crop yield

Crop Yield

The total quantity of crop that the land produces

Bioaccumulation

The build-up of toxic substances in living organisms

What do quantities sampling do

Estimates population

How to make a test valid.

Random

How to make a test reliable

Repeat

why would a predator population grow

if the prey population grows because then they have a bigger food supply

where does the oxygen go in the light reaction

after its seperated from hydrogen it leaves out through the stomata into the atmospehere, the rest is used by the mitochondria for aerobic respiration

what is sugar used for in plants

to form starch, cellulose, energy source, combine sugar with nitrates to make amino acids,

How to test for starch in a leaf

Heat leaf in boiling water for 30 secondsHeat it in boiling ethanol for a few minutesWash with water and add iodine solutionAfter a few minutes, the parts of the leaf that contain starch turn blue-black.

what can we use instead of pesticide and fertliser

gm and animal predators

Bioaccumulation

the build up of a substance as it passes through a food chain like ddt

how can the chance of getting a mutation be increased

radiation, chemicals

Variation occurs as a result

of mutations that create new alleles of genes.

biotic factors affecting biodivercity

predation, grazing, development of towns, increasing human population

how to measure the rate of photosynthesis

measure amount of CO2 used or measure amount of O2 produced, in a certain timeputting plant underwater and counting how many bubbles produced

what happens to animal if no adaptations

fails to survive since its eventually out competed by another speicies

Mitosis

Process of cell division

Chromosomes

Threadlike structures made of DNA molecules found in the nucleus

Chromosome complement

The number of chromosomes present in the nucleus of each body cell (46 in a human).

Chromatid

One of two identical "sister" parts of a duplicated chromosome. Separate during mitosis

Spindle Fibres

Threads produced during mitosis to pull chromatids apart.

Equator

The centre of the cell where chromosomes line up during mitosis

Stem Cells

Unspecialised cells that can make new copies of themselves and develop into different specialised cells

Specialised cell

A cell in a multicellular organism that is adapted to carry out a specific function, e.g. red blood cell

Tissue

Cells of the same type working together, e.g. muscle

Organ

Several different tissues working together to carry out a particular function in the body

Organ system

A group of organs working together, e.g. the immune ...

Hierarchy in Multicellular Organisms

cell \> tissue \> organ \> organ system \> organism

Stimulus

Something that sets of a reaction in the nervous system, e.g. light or sound

Neuron

A nerve cell. Carries a message by an electrical impulse.

Central Nervous System (CNS)

Part of the nervous system made up of the brain and spinal cord.

Synapse

Gap between two neurones. Chemicals carry the message across. this gap.

Motor Neuron

Nerve cell that transmits electrical impulses from the CNS to effectors such as muscles

Inter Neurone

Nerve cell located in the spinal cord that transmits electrical impulses from a sensory neurone to a motor neurone.

Sensory Neurone

Nerve cell that transmits electrical impulses from a sense organ to the CNS

Reflex

Rapid, protective response to heat or pain

Reflex Arc

Movement of an electrical impulse from a sensory receptor via a sensory, inter and motor neuron to an effector such as a muscle

Cerebrum

Part of the brain which processes sensory input and controls conscious thought.

Cerebellum

Part of the brain which controls balance and muscle co-ordination.

Medulla

Part of the brain which controls breathing and heart rate.

Endocrine

Glands which secrete hormones.

Target Organ

An organ whose cells have receptors for a particular hormone.

Insulin

A hormone released by the pancreas which acts to reduce high blood glucose levels. Target organ is the liver.

Glucagon

A hormone released by the pancreas which acts to increase low blood glucose level. Target organ is the liver.

Pancreas

Organ which produces the hormones insulin and glucagon.

Glycogen

A complex carbohydrate formed in liver cells from stored glucose

Liver

Large organ which stores glucose as glycogen.

Diabetes

Condition which results when body is unable to control blood glucose levels.

Sexual Reproduction

A reproductive process that involves the fusion of gametes from two parents to combine their genetic material to produce a new organism, which differs from both parents.

Gamete

Haploid sex cells.

Testis (testes plural)

Organ in animals that produces the male gamete, sperm

Haploid

A cell with one set of chromosomes (23 in humans)

Diploid

A cell with two sets of chromosomes

Ovary (animals)

Organ in animals that produces the female gametes, the egg

Sperm Cell

Male sex cell produced in the testes of animals.

Egg Cell

Female sex cell produced in the ovaries of animals.

Anther

Part of a flower that produces the pollen

Ovary (plant)

Part of a flower that produces the female gametes

Pollen

The male gamete of a plant