VCE Biology Unit 2 Area of Study 01 Adaptations of Organisms Chapter 13.1 Environmental factors and adaptations

13.1 Challenge to survival Living organisms require: Nutrients Water O 2 and CO 2 Light Temperature Tolerance Range (for each requirement) is range where organism is functioning most efficiently

13.1 Challenge to survival Environmental factors Physical – abiotic environment Soil Rainfall Temperature Salinity etc.

13.1 Challenge to survival Environmental factors Biological – biotic environment Predators Food (prey) Mates Competitors e.g. Page 243 Table 13.1

13.1 Challenge to survival Anyone of these factors can be the ‘limiting factor’ (i.e. the one that is limited in supply). E.g. water, food, mates, etc. Tolerance range affects distribution. E.g. Change in temperature may lead to a change in distribution of a particular plant species.

13.1 Challenge to survival Adaptation: Organism show a change in physiological (functional), anatomical (structural) and/or behavioural adaptations that allow them to survive and reproduce in changing conditions (both external and internal). An adaptation is an inherited change in characteristics that increases the chance of survival and reproduction in a changing environment.

13.1 Challenge to survival Acclimatisation: This is NOT adaptation This is a temporary change to an organism’s physiology and is not inherited. E.g. Climbing Mount Everest – Acclimatise at camps at different altitudes. Haemoglobin increases due to decrease in O 2. Changes back afterwards.

13.1 Challenge to survival Australian Environments: Terrestrial (land) (page 247) and aquatic (fresh water and marine).

13.1 Challenge to survival Australian Environments: Terrestrial (land) North East coast (Northern Queensland and Eastern Northern Territory) – tropical, wet summers (2,000 mm of rain per year). South coast – temperate, cool winters, temperatures range from -2°C to 43°C. Inland – semi-arid to desert. High temperatures, low rainfall. Old continent – low levels of nutrient in soil.

13.1 Challenge to survival Australian Environments: Aquatic (fresh water and marine) – fresh rivers and inland lakes can dry up in summer. Marine varied conditions. North – tropical coral, South cold rugged, rocky coastline.