Adaptation and Acclimatisation Flashcards
What is natural selection?
Random variation by chance will produce a useful trait
Organism more likely to survive and reproduce
Passes trait onto offspring
Adaptation spread through population
What is adaptation?
A trait that increases the fitness of an organism in its environment
May be morphological, behavioural or physiological
What is an example of morphological adaptation?
Darwin’s finches
What is an example of behavioural adaptation?
Hibernation
Arose due to food scarcity in winter
What is an example of physiological adaptation?
Oxygen conservation in sperm whales:
Slow heart rate
High density of red blood cells
Oxygenated blood can be directed to the brain only
Myoglobin is abundant - stores oxygen is muscles tissues
What are the differences in oxygen and pressure in high and low altitudes?
Low altitudes:
High atmospheric pressure
High atmospheric oxygen
High altitudes:
Low barometric pressure
Low atmospheric oxygen
Fewer oxygen molecules per breathe of air
SAME PERCENTAGE OF OXYGEN MOLECULES IN BOTH ALTITUDES
What is acclimation?
Physiological compensatory response to environmental change
What are the basics of acclimation?
Short-term response to a single environmental variable
Not heritable
May be instant or built over time
Often a response to an experimental or artificial condition
PHENOTYPICAL NOT GENETIC RESPONSE
What is acclimatisation?
Physiological compensatory response to multiple elements of environmental change
What is plasticity?
Ability of living organism to change their state in response to any stimuli
What are the basics of plasticity?
Occurs at any level of complexity e.g. molecular, cellular, behavioural etc
Limited in genetically determined bounds
Acclimation and acclimatisation are types of plasticity
What is oxygen saturation?
The percentage of haemoglobin binding sites that carry oxygen
If all binding sites occupied, 100% oxygen saturation
How is oxygen transported?
In the lungs:
high partial pressure of oxygen
haemoglobin has high affinity
oxygen binds readily
In the muscles:
low partial pressure of oxygen
haemoglobin has low affinity
oxygen is released
