Adaption and evolution Flashcards
How have desert animals adapted?
Large surface area to lose heat
Concentrated urine, little sweat
Camels store fat to have water in the desert
Large feet to spread their weight over sand
How have arctic animals adapted?
Small surface area to conserve heat
Thick fur
Large feet to spread on the ice
How have cacti adapted to the desert?
Spines instead of leaves to reduce water loss
Stores water in thick stems
Shallow but matted roots to absorb things quickly
Give an example of a physical and chemical defence for a plant
Thorns for physical
Poisons for chemical
What is classification?
Organising living organisms into groups (depending on genetic material)
What are the subcategories in a kingdom? (Eg animal kingdom)
A genus
A species
What is a Genus?
a group of closely-related organisms
What is a species?
A group of closely related organisms that can breed with each other
What defines a plant and animal?
Plants have chloroplasts and produce their own food
Animals have compact bodies and need to find their food
What are vertebrates and invertebrates?
Vertebrates have a backbone and an internal Skeleton
Invertebrates don’t but can have an exoskeleton
What are the 5 types of vertebrates?
Fish Amphibians Reptiles Birds Mammals
What is an ecosystem?
Where different organisms live together in an environment
What is the difference between a natural and artificial ecosystem?
A natural ecosystem is where humans don’t control anything going on within it
An artificial one is where humans deliberately promote the growth of certain organisms and get rid of others
What is a quadrat and what is it used for?
A square frame enclosing a certain area
You use it to estimate a population size for an ecosystem
Why is the quadrat method not so accurate?
How could you make it more accurate?
It only represents a certain area and this may vary throughout the ecosystem
To make it more accurate you would use a larger quadrat
What is a hybrid?
A hybrid is when you cross breed two species (eg a horse and donkey makes a mule)
However they hybrid will be infertile so it is not a new species
What is population size limited by?
The total amount of food or nutrients available
The amount of water available
The amount of light for plants
The quality of shelter
Why does the population of prey and predator go up and down?
If the population of prey increases, the population of predators will also increase
However, as predators increase, prey will decrease, leading to a decrease in predators
A decrease in predators allow prey to rise again
What are parasites?
Something that is dependent on another life form, so takes from them without giving back (eg tapeworms)
What is mutualism?
When two organisms depend on each other and BOTH benefit
What is the ‘primordial soup’ theory?
Proteins pool together in the ocean and get struck by lightning, forming the first amino acids
How have moths adapted in the industrial revolution?
Before, white moths were better as they camouflaged in, whereas black ones were killed
When the industrial revolution started, everything was coated in dust so black moths were better
What are the three ways a species can become extinct?
The environment changes too fast for them to adapt
A new predator or disease kills them
They can’t compete with another species for food
What were Darwin’s 4 observations?
All organisms produce more offspring that could possibly survive
Population numbers tend to remain fairly constant
Organisms in a species show wide variation in characteristics
Some of the variations are inherited and so passed onto the next generations
