Topic 7 - Classification and Biodiversity Flashcards
What is classification?
Classification is the grouping of organisms by comparing their similarities and differences.
What is a species?
A group of organisms that can reproduce to have viable offspring.
What is the Linnaean system?
KPCOFGS
How has technology affected classification?
Led to new, more accurate classification systems, based on sequencing the DNA (genetic material) and proteins of organisms.
What is the Linnaean system based on?
Morphology and anatomy
Which 2 groups can animals be divided into?
Vertebrates and invertebrates
What is a vertebrate?
Any animal with a backbone.
What is an invertebrate?
Any animal without a backbone.
What are the 5 classes of vertebrates?
Birds Reptiles Amphibians Mammals Fish
What defines a “bird”?
Birds have feathers, two wings, two scaly legs, lay hard-shelled eggs on land and have lightweight bones.
What defines a “reptile”?
Reptiles lay waterproof eggs on land, have dry, scaly skin. and, excluding snakes, have four limbs.
What defines an “amphibian”?
Amphibians lay eggs covered in jelly, in water, have moist scaleless skin, webbed feet, and perform gas exchange through their lungs and skin.
What defines a “mammal”?
Mammals have mammary (milk) glands, sweat glands, four limbs, hair or fur and give birth to live young.
What defines a “fish”?
Fish have scales, fins, a lateral line and gills for gas exchange in water.
What are the two types of plants?
Ferns and flowering plants
What defines a “fern”?
Ferns don’t have flowers or seeds and reproduce asexually using spores.
What defines a “flowering plant”?
Flowering plants can reproduce asexually or sexually and may produce seeds in their ovaries.
What is an adaptation?
Any trait helping organisms survive better in the environment in which they live.
What are the types of adaptation?
Morphological and behavioural
What is a morphological adaptation?
Changes to physical features, like structure or shape, affecting how an organism looks.
What is a behavioural adaptation?
Changes that affect an organism’s lifestyle or actions.
What is an example of a morphological adaptation?
White fur in polar regions, waxy cuticles to reduce water loss.
What is an example of a behavioural adaptation?
Hibernation, mating calls.
What is competition?
A relationship between organisms striving for the same resources in the same place.
What do animals compete for?
Mates, food and territory
What do plants compete for?
Water, minerals, light, space
What affects population growth?
Disease, pollution, food supply, predation
What is biodiversity?
The variety of different species and the numbers of individuals within those species in an area.
How does biodiversity impact the economy?
Biodiversity provides the income of millions of the poorest people around the world e.g. ecotourism.
How does biodiversity impact morals?
Many people feel guilty about the environmental destruction and suffering to other species that humans are responsible for.
How does biodiversity impact ecosystems?
More biodiverse ecosystems are more stable, with greater genetic diversity, for selective breeding or genetic modification, and are often important for protecting humans from environmental disasters.
How does biodiversity impact health?
Biodiverse ecosystems are valuable sources of medicine, food, clean water and other resources and materials needed in everyday life.
How can endangered species be conserved?
Controlling alien species, maintaining seed banks, monitoring and protecting habitats
What is an alien species/a biological control?
A species that was introduced (normally accidentally) by humans into a habitat usually to control a pest.
How does maintaining seed banks help conserve endangered species?
Seed banks are special storage facilities for different seed types that help preserve the genetic diversity of plants.
How does monitoring and protecting habitats help conserve endangered species?
Involves passing legislation which make certain activities in these habitats illegal which can be controversial when a habitat lies across multiple countries that must cooperate to protect it.
How can biodiversity be measured?
Quadrats and transects
What is a quadrat?
Quadrats are square frames that can be used to estimate population sizes.
What is a transect?
Used to investigate the effect of a factor on the distribution of a species, a transect line is a piece of tape that is stretched across the habitat of interest.
Quadrats are placed at regular intervals along the transect line.
Estimating a Plant Population Size 1
Divide the habitat up into a series of quadrat-sized cells.
Estimating a Plant Population Size 2
Randomly select a given number of cells, then go out into the habitat and place the quadrats in these positions.
Estimating a Plant Population Size 3
To evaluate the quadrat contents, either count the number of individual organisms of interest or record the percentage of the quadrat taken up by an organism.
Estimating a Plant Population Size 4
The samples from the quadrat are used to estimate the total population in a given area.
What is the equation for estimating a plant population size?
Population = number counted x (total survey area / area sampled)
Why aren’t quadrats used to measure animal population size?
Most animals are more mobile than plants, so they can’t be accurately sampled.
What is capture-recapture?
Animals are caught, marked and then released. Then another sample is taken, and the number of recaptured animals (those that have been marked) is recorded. This gives information on the population size.
What are pooters, nets and keys?
Pooters and nets can be used to catch crawling insects and flying animals, respectively. Keys can then be used to identify organisms.
What is the equation for estimating an animal population size?
Population = (1st sample x 2nd sample)/2nd sample previously marked
When using capture-recapture, what do you have to assume?
There is no death, immigration or emigration, the sampling methods used are identical, the marking has not affected the survival rate of the animals
What is interdependance?
When species depend on each other for pollination or seed dispersal.
How can biodiversity be maintained?
Breeding programmes, preventing extinction, protection and regeneration of rare and threatened habitats, farmers maintain field margins and hedgerows, recycling, slows down expansion of landfill sites, reduces extraction of new resources.
