chapter 10 - adaptations and diversity Flashcards
unit 2 aos 2
abiotic factors
non-living factors
eg temp, wind, water
biotic factors
living factors
eg animals, plants, fungi
animals: structural adaptions to hot temps
-insulation: more insulated, harder it is to release heat
-sa:v ratio: high releases or absorbs large amount of heat in little time
animals: physiological adaptions to hot temps
-metabolic heat: endotherms spend energy producing metabolic heat, ectotherms obtain heat from environment
-surface blood flow: when internal temps rise, blood vessels dilate, cooling animal
-increase water input
-decrease water output
-evaporate cooling
animals: behavioural adaptions to hot temps
-evading extreme conditions
-enduring extreme conditions
plants: adaptions to hot temps
plants must:
-decrease heat intake: having light-coloured/reflective leaves, producing leaves with small sa:v ratio, having leaves vertical
-maximise water uptake: deep or horizontal root systems
-minimise water loss: reducing water lost via stomata
challenges of cold environments
-low temps
-piercing winds
-low availability of nutrients
-precipitation as snow
animals: structural adaptions to cold temps
-insulation: thick layer
-sa:v ratio: reducing ratio releases heat slowly
animals: physiological adaptions to cold temps
-endotherms vs ectotherms: endotherms are more common in cold and it’s easier to maintain internal body temp
-torpor: hibernation and brumation allow animals to survive on little food or water, avoid harsh weather
-circulation: vasoconstriction (reduced diameter of small blood vessel) and counter current circulation
counter current circulation
-uses heat in blood travelling from heart, to heat the cold blood returning from animal’s periphery
-this cools blood heading towards periphery
animals: behavioural adaptions to cold temps
-reducing exposed surface area
-huddling
-seeking shelter
-migrating to warmer climate
problems plants have with freezing
-enzyme and protein driven reactions progress slowly at lower temps
-formation of ice crystals rupture cell membrane and other cell contents, plant vascular systems are blocked with ice
how plants prevent freezing
-when temps drop, plant cells deceive signals to increase concentration of solutes in their cells, increasing a plant’s resistance to freezing
-cold adapted plants can produce antifreeze proteins, disrupts formation of ice crystals
deciduous trees
-seasonally drop all leaves to avoid harsh conditions
advantages to evergreen trees:
-avoids freezing leaf tissue during winter
-requires less energy and water to survive during winter
-experiences less branch breaking
seed dormancy
-dormant seeds are unable to germinate during a specific time under certain environmental conditions
-trait of many cold adapted plants - seeds dispersed before winter and remain dormant until warmer months
ecosystem
multiple communities interacting with one another and their physical environment
ecological organisation
-cell: individual cells of a larger organism
-organism: individual living thing
-population: a group of organisms of the same species living in the same geographical region
-community: a group of interacting populations of different species in the same geographic region
-ecosystem: multiple communities interacting with one another and their physical environment
population size
total number of members within a given population
carrying capacity
a limit to how many individuals an environment can support and sustain
population growth model
Ni + 1 = Ni + births - deaths + immigration - emigration
Ni + 1 = future population size
Ni - initial population size
factors that can alter population size
-births
-deaths
-immigration
-emigration
population distribution
a species’ geographical spread across different areas
-limited by ideal habitat of species and its ability to tolerate different environment
-can be uniform, random, or clumped arrangement
-can change due to environmental factors
population density
the number of individuals found in a given area
-some factors can influence populations regardless of population density
density independent factors
-properties of the environment that are unaffected as density changes (eg climate)
-this factor will have the same effect on two populations of different density
