24

Question 1

biogeochemical cycles

Answer 1

chemical reactions necessary for the growth and development of living systems

biological,geological and chemical interactions

Question 2

carbon cycle

Answer 2

cycles form land water biota industry into the atmosphere and back again , ocean is the largest sink storage

plants, algae and bacteria convert atmospheric CO2 into unstable compounds i.e. photosynthesis = sugars

Question 3

Ecosystem - abiotic components - solar energy

Answer 3

solar energy enters ecosystem via photosynthesis - chlorophyll - green pigment in plants where light stimulates photochemistry
limitations on photosynthesis are temperature optimized at 30C and water availability

Question 4

ecosystem - biotic components

Answer 4

The abiotic components of an ecosystem provide the life support for the biotic components
producer - plants/autotrophs are capable of using carbon dioxide as source of carbon for food growth

consumers- animals/heterotrophs - depend on other organisms mainly producers as source of carbon,

Detritivores - detritus feeders and decomposers- worms, bacteria,fungi etc- release inorganic compounds and nutrients by breaking down organic material

Question 5

ecosystem components - community

Answer 5

community

- population of plants and animals that interact at a particular time and location

Question 6

tolerance range

Answer 6

the range of environmental conditions that are tolerable for survival in a species such as climate, soil and vegetation

Question 7

optimal range

Answer 7

best condition within the tolerance range in which species are at their healthiest state

Question 8

biotic components species interactions

Answer 8

Competition - species compete for food and space
Predation - stable ecosystems need predation for population control
Amensalism - inhibition of one species by another

Question 9

Adaption and Evolution

Answer 9

Earths ecosystems are dynamic
- change can be gradual (climate change) or catastrophic (volcano, asteroid) and communities must adapt or evolve to survive

Question 10

Biodiversity

Answer 10

diversity among the species population in an ecosystem including species diversity, genetic diversity and ecosystem diversity

Question 11

loss of biodiversity

Answer 11

due to habitat loss, over exploitation, population, fishing , urban industry, water use and energy and transport

Question 12

conserving biodiversity

Answer 12

biosphere reserves - areas promoting solutions to reconcile the conservation of biodiversity with its sustainable use
convention on biological diversity
research - DNA barcoding, conversation strategies and cloning or d’extinction

Question 13

habitats

Answer 13

• type of environment where an organism resides or is biologically adapted to live

Question 14

Symbiotic relationships

Answer 14

Symbiotic relationships - interactions between two or more organisms living closely together
mutualistic - both organisms benefit (sharks and pilot fish)
commensalism - one organism benefits the other ris neutral (i.e. bird nests)
parasitism - one organism benefits and the other is harmed (i.e. strangler fig tree)