varying populations & human populations

Varying Populations & Human

PopulationsBy Nick Logan

A load of boring Biology terms you need to know….O Environment – Set of conditions which an organisms

exists in – containing abiotic and biotic componentsO Abiotic – Non living factorsO Biotic – Living factorsO Habitat – The place within the ecosystem that an

organism lives inO Ecosystem – Made up of a community of living

organisms and biotic factorsO Community – is all the populations of different

organisms living and interacting in a certain area at a certain time

O Niche – Where an organism is found within the habitat AND how that organism fits into its environment. Its role in a habitat

http://www.youtube.com/watch?v=qIMwJ1l0PGE&t=0m9s

O Population – A group of interbreeding organisms belonging to the same species

Varying PopulationsO Sigmoid Population Curvehttp://www.youtube.com/watch?v=Vpt34kNFn9k

Population SizeO Limiting Factors, such as….?

They can be either abiotic or biotic factorsO Temp, light, pH, water concentration,

humidity

O Competition, predation

HUMAN POPULATIONS!!!

O Cheeky bit of Attenborough……http://www.youtube.com/watch?v=LwgO3i_M0tY&feature=related

O Basic Factors that Affect Human Population?

Factors that Affect Birth Rate

O Economic conditionsO Cultural & Religious BackgroundsO Social PressuresO Birth ControlO Political Factors

Factors that Affect Death Rate

O Age profileO Life expectancy at birth (IFM)O Food supplyO Availability of safe drinking waterO Effective sanitationO Quality of medical careO Natural disastersO Wars

Population StructureO Demographic Transition Model

- change in societies from a……

Population PyramidsO Stable Population

- birth and death rate are in equilibrium. Therefore no change in population sizeO Inc. Population

- high birth rate = wide base- typical of LEDC’s

O Dec. Population- low birth rate = narrow base- lower mortality rate = more old people- occurs in MEDC’s