Biology Flashcards
Three levels of consumers
Producers are…
Primary: herbivores
Secondary: carnivores
Tetiery: omnivores
serve as source of food for food chain
Why do we need to save biodiversity?
Ecosystems serve humans because they provide natural functions such as microbes vital to break down recycle
Importance of renewable energy
Create job, abundant, easy, environment friendly
Biodiversity:
The variety of life in a habitat
Eutrophication:
Depletion of oxygen in the water due to enrichment of minerals in water
Stimulate growth in aquatic life
Pollution:
Disruption of natural world by chemicals or agents
Carbon cycle:
Important because of living organisms composed of compounds of it
Carbon dioxide used for PHOTOSYNTHESIS
Oxygen released into atmosphere
Carbon and oxygen atoms in glucose are CONVERTED INTO COMPOUNDS FOR CELLULAR REACTION in living organisms
On death, compound recycled by DECOMPOSERS
Nitrogen cycle
Proteins to use nitrogen to form cell membranes
Vital for dna
1/ nitrogen in soil
2/ nitrogen compound in food Cain
3/ after death, decomposed return nitrogen into soil
Agal blooms
Fertilisers harm environment
Rain wash fertiliser in lake
Algae grows excessively.
Algae die, decomposition of bodies use up all oxygen and aquatic life suffocate and die
Greenhouse effect
Permafrost Sea level Sea ice Ocean acidification Changed biodiversity CFCs & Ozone layer
Cell theory
1/ all cells are made from prehistoric cells
2/ all living things are made of cells
3/ cell basic unit of life
Define disease:
A disorder of function of living body that affects specific area of body
First line defence
Specific Skin, hairs Salt Blood clot Cilia expel caught microorganism
2nd line of defence
Non specific
Phagocytes
Inflammation
Skin swelling from phagocytes leaving capillaries and into infected tissue
Inflammation makes blood vessels large so more phagocytes can remove foreign bacteria
3rd line of defence:
Specific
Pathogens carry foreign chemical called ANTIGEN
lymphocytes carry specific chemical fit specific antibody & B cells
B cells memorise virus
Neurone cell
Dendrite Axon Myelin sheath Synaptic bulbs Nucleus
Receptor cells
Neurotransmitter chemicals
Allele:
alternating form of gene
Artificial selection
Selective breeding of organisms
Carrier
Organisms carrying a recessive allele
Diploid:
Cells consisting of two sets of chromosomes
Dna
Deoxyribonucleic acid
Found in nucleus
Evolution
Genetic change in organism which lead to new species
Gene
Molecular unit of heredity
Genome
All the genetic info processed by organism
Heterozygous: individuals with different alleles
Homozygous…
Individuals that inherit identical genes
Genotype:
term referring to genetic composition of the organism for a trait