Biology cards from chapter 12 of McGraw-Hill ryerson text, grade 12
What type of species are humans?
k-selected: few offspring, mature reproductive age, parental care
What is demography?
The study of statistics related to human population size.
What are factors that have affected population growth?
Improved agricultural methods, weapons to kill predators, medicine, better shelter: cause change of logistic to exponential
What is doubling time?
The time it takes for a population to double in number.
Describe the 3 types of population pyramids:
Growing - triangular
Stable - rectangular
Shrinking - upside down triangle
What is an ecological footprint?
The amount of productive land that is required for each person in a defined area for food, water, transportation, housing, waste management and other requirements.
What 6 categories does an ecological footprint include?
cropland, grazing land, fishing grounds, forest land, carbon absorption land, building area
What is the estimated ecological footprint per person?
10 000 m2
In developed countries what are the largest parts of footprint?
1. energy production 2. food production 3. forestry requirements (results from need to absorb co2 from emission of fossil feuls)
What is the available biocapcity? What does it entail?
Earth's carrying capacity for human population. Includes cropland, grazing land, fishing grounds, forest land, carbon absorption land, building area
What is mercury contamination?
In addition to the combustion of coal releasing harmful gases, toxic metals such as mercury are released, entering waterways, microorganisms convert it to methyl mercury, easily absorbed by organisms and biomagnified up the food chain
What are the effects of high levels of methyl mercury?
Interferes with growth, development, reproduction, damages immune and nervous systems leading to death.
What is one solution to reducing the amount of toxic mercury that is released?
use more renewable forms of energy such as wind, solar and hydroelectric.
What is deforestation?
The clearing out of trees so land can be used as pasture land or cropland
Why is the abundant rainforest a bad site or cropland?
Tropical land has poor soil, only fertile for 10-20 years. In rainforests the water needed by organisms is recycled thru it's biotic components and rarely reaches soil: abundant rain and bacteria move this process along.