Quick questions on Adaptations of plants and animals to their environment: VCE Biology Unit 1

Desert (xerophytes). Cacti, Australian spinifex, saltbush.

Desert. Camels, kangaroo rats, fennec foxes, dingoes.

A red kangaroo in the Australian desert and an Adelie penguin in Antarctica face opposite challenges (overheating vs freezing). The kangaroo has structural adaptations to lose heat (thin coat, blood vessels close to the skin in the forearms which it licks to evaporative-cool), physiological adaptations (long Loop of Henle to concentrate urine, sweating in mild heat), and behavioural adaptations (resting in shade during the day, foraging at dawn and dusk). The penguin has structural adaptations to retain heat (thick blubber, dense overlapping feathers, small flippers), physiological adaptations (countercurrent heat exchange in legs), and behavioural adaptations (huddling, rotating the outer ring of the huddle).

Adaptations are the result of long-term natural selection: individuals with heritable traits that improve survival and reproduction leave more offspring. Over generations, the frequency of those traits rises in the population. Adaptation explains the extraordinary fit between organisms and their environments (covered in detail in the Unit 4 evolution dot points).

Physical features of the body. Examples: a camel's long eyelashes, a polar bear's thick fur, a cactus's spines.

Internal biochemical or physiological processes. Examples: countercurrent heat exchange, antifreeze proteins in Antarctic fish, sweat production, CAM photosynthesis.

Inherited actions or responses. Examples: migration, hibernation, nocturnality, schooling, courtship displays.

Cacti, Australian spinifex, saltbush.

Mosses, lichens, low-growing tundra plants.

Mangroves, saltbush.

Polar bears, penguins, Antarctic fish.

Acclimation is a reversible short-term change in an individual (sweating more after a few weeks in a hot climate). Adaptation is heritable and acts across generations.

Adaptations are not designed and not chosen by the organism. They are inherited variations that happen to work.

A vestigial structure (such as the human appendix) was once adaptive but is no longer; some features are byproducts of development, not adaptations.

A long Loop of Henle is the structure; its ability to concentrate urine is the physiological adaptation. Both can be cited, but be clear which is which.