Adaptations Flashcards
what is an adaptation?
Genetically controlled.
Structural, behavioural or physiological.
It enhances the survival of an organism in particular environmental conditions.
what are the two challenged to adaptation and survival?
Biotic: mates, competition, parasites.
Abiotic: water, oxygen, temperature, soil, gas, humidity.
what is the tolerance range?
Every organism has tolerance to factors such as temperature, desiccation (drying out), oxygen concentration, light intensity and UV exposure.
Any factor that exceeds the limit of tolerance is a limiting factor.
The tolerance range defines the environment in which an organism can live.
what is a limiting factor?
Any condition that approaches or exceeds the limits of tolerance
what are properties of water?
Cohesive- stick together.
It is the predominant solvent.
Restricts temperature change and has a high heat of vaporisation (evaporation).
Solid water is less dense than liquid water.
what is high heat of vaporisation? how does this help cool animals down?
High heat of vaporisation is an important factor in cooling animals with heat stress (kangaroos lick themselves).
Heat energy needed to evaporate the water is taken from warm blood close to the skin which cools the blood and thus the core.
what are adaptations for survivng in a desert? how is water gained and lost?
Survival without drinking: eating things with water, concentrated urine, few sweat glands (structural), dry faeces (physiological).
Water gain: dew, burrowing to stop water loss, metabolic water.
Water loss: evaporation from skin, faeces, loss in exhaled air, urine, milk from mother.
how does survival by dormancy work?
Some frogs make a moist burrow in sealed clay with mucus when water dries up.
They can be buried for 1-2 years.
how does survival by moving around work?
move to where more resources are
what is an example of surviving through offspring?
producing drought resistant eggs
what is temperature related stress?
Animals in hot environments often experience stress due to body temperature, water and salt balance.
how does hibernation help species in the cold? what is it triggered by?
Hibernation.
They reduce energy requirements and can be protected.
It is triggered by scarcity of food, lowing of temperature, endocrine responses to changes in the day light cycle.
Sudden or large environmental changes.
Temperature is reduced but always above freezing (no movement).
The temperature in the burrow is relatively constant.
why can ice damage or kill? how is this solved?
Reactions essential to life occur in liquid water, they can not occur in ice.
When water freezes, it expands, frozen cells rupture.
Water with salt doesn’t freeze until about -18 degrees.
Some organisms make an anti-freeze with glycerol, amino acids, sugars or mixtures.
They are released into their body fluids.
how do animals keep warm with adaptations?
Penguins huddle (behavioural). Insulation (fat/fur). Antifreeze chemicals. burrows. Metabolic heat.
what adaptations do mammals in water have?
Oxygen storage in lungs and in body tissues- more red blood cells.
Insulating layer of fat or blubber.
Antifreeze proteins circulate in the blood.
what are some adaptations in plants?
Maximise water uptake.
Minimise water loss: transpiration through the stomata must be limited (rolled leaf or hairy leaf)
Produce drought-resist seeds.
Silver or glossy leaves reflect more light and lower leaf temperature.
Small narrow or cylindrical leaves have more surface area so gather less heat in the sun and lose less water.
Thin parts of leaves lose more heat. Leaves that have more thin margins or edges get less hot and lose less water.
Leaves that hand vertical also obtain less sunlight directly and get less hot.
what are some adaptations of leaves? (4)
Succulents such as prickly pares have no leaves. They can store lots of water in their thick bodies.
Trees with fine needles can prevent build up of snow on them.
Salt bushes excrete salt crystals onto their leaves which reflect light. They also have sunken stomata and are covered in hairs and have good leave orientation.
Rolled up leaves to prevent water loss.
how do plants survive in the cold and ice?
When ice forms in living plant tissue, water leaves cells and adds to the ice.
The ice grows in the gaps between cells.
Though the ice punctures the the cell walls, the membranes are just pushed back and the cells stay intact.
The inside of the cell doesn’t freeze because of the concentration of ions in the cytosol lowers freezing temperature.
what are problems with plants growing in water? what do they do to cope?
Problems- lack of oxygen and lack of light if submerged.
They may have air- filled spaces for buoyancy.
Stomata may be on the upper side of the leaf.
There may be a thin cuticle for diffusion of gases.
what are adaptations plants use to move controlled by hormones and turgor pressure?
Tropisms- a plant growth in response to an environmental factor and has a direction (plants grow towards sun).
Nastic movement- movement of a plant in response to an environmental stimulus but not in the direction of that stimulus.
where do mangroves live and what do they need to adapt to?
Grow in intertidal zone on shallow muddy shores.
They need to adapt to: changing salinity levels with the movement pf tides or from total rivers, lack of oxygen to their roots in waterlogged soil, boggy and unstable soil that makes anchorage hard, seed dispersal in an aquatic environment.
how do mangroves get rid of salt?
Exclusion: actively pump salt out across the membranes of roots.
Excretion: from glands in leaves.
Accumulation.
describe the specialised roots of mangroves.
Oxygen normally enters roots through lenticles which are rough spots consisting of loose, corky tissue through which gases can diffuse.
They have evolved aerial roots that all have lenticles (peg roots, pneumatophores and stilt roots).
Pneumatophores increase the surface area exposed to the air at low tide for maximum oxygen uptake
Aerial roots with cable roots that spread laterally to stabilise the plant in soft mud.
Cable roots have a mat of fine, hair-like roots that absorb nutrients and water.
how do mangroves disperse their seeds?
Seeds of mangroves are buoyant.
Some mangroves are viviparous.
Viviparity means that the seed germinates and develops while still attached to the parent plant.
It falls into the water when it has a developing root system.
This enables it to anchor itself before washed into the waves.
what is classification?
Each organism can be names and placed into particular groups- taxonomy.
what are aspects of biological classification?
Diversity
Evolution
information
International sharing of information
what is biodiversity?
Variety of life forms, plants, animals, microorganisms and ecosystems they inhibit.
what does recording allow us to do?
Recording allows us to know of species existence, which species are most endangered, which need protection and which can be used safely for the benefit of people.
what is species diversity?
: variety of different kinds of organisms in a particular habitat or region.
what is genetic diversity?
variety of genes or different inherited characteristics.
what is ecosystem diversity?
variety of physical environments.
why is the binomial system used? what is it? what is it made up of?
Scientists need to refer to species the same way to understand and communicate.
Species are referred to by their scientific name.
It is a two part name- binomial.
Genus and then species (lower case).
what is a genus?
many species
what is species?
Differences in morphology (form/structure) are used to divide organisms into species.
Biological species are able to reproduce and have fertile offspring.
what is biological classification? (2)
Linnaean system is a hierarchy placing species into groups that are increasingly more inclusive.
At each level the difference becomes greater.
eg. kingdom, phylum etc.
what are subspecies?
slight variation in form across different locations.
what is a hybrid?
offspring of two interbreeding species, most are sterile.
what is phylogenetic classification?
Patterns of morphology or genetic characteristics can be represented in a branching phylogenetic tree.
Shows evolutionary relationship between organisms.
what are the five kingdoms? what is a newer idea?
Protista (unicellular eukaryotes) Plantae Animalia Fungi Monera (bacteria prokaryotes) domains
what are the three domains?
Bacteria
Archaea
Eukarya
what are tools for classification?
Field guides
Data base
Reference collection
Dichotomous key- using recognisable features
how is genetic material being used to classify?
Increasingly genetic material is being used for identification.
Look for the presence of known markers.
Use hair follicles, tissue, blood, scats.
DNA bar coding.
DNA sequences can show variation over the geographical range of the species.
why should biodiversity be managed?
Aesthetic
Ecological value: plants produce and provide, animals pollinate and provide food, microorganisms decompose.
Practical value: food, medicine, industrial needs, breeding stocks, crop pollinators, diversity in genes, future resources, biomimicry.
why should habitats be conserved?
Save species from extinction.
Inter-relationship of species.
what are strategies for managing the earth’s biodiversity?
Conservation of species: under threat of extinction. Ecological importance. Economic value. Cultural of social importance (in situ- in natural habitat, ex situ- in captivity).
Establishing protected areas:
habitat loss.
National parks.
Prevention and control of invasive species:
pest organisms- foxes, rabbits, cane toads etc.
Biological control- use of natural predator, parasite or pathogen.
what are examples of technology that control pest species?
Infecting rabbits with a virus that includes a modified gene that stops conception in females.
Carp- a gene is switched off in females so that they only have male offspring.
how can pollution be managed?
Reduce industrial waste. Reduce use of fossil fuels. Energy efficient appliances. Environmentally friendly products. limit use of chemical fertilisers, herbicides and pesticides.
what is climate change caused by?
increase in CO2 levels
how does overexploitation occur?
Food Construction Industrial products Fashion Medicine
how can resources be used sustainably?
Resources are consumed no faster than they can be replaced naturally.
what is bioprospecting?
Search for new plant and animal substances for medicines or other uses.
anti-cancer properties
Fight-disease
Many medicines are found in the Amazon
how is an equilibrium maintained in the body?
by homeostasis
what is homeostasis? what environments does it involve? how is it maintained?
The maintenance of a relatively stable internal environment in the face of a changing external environment.
Involves internal and external environments.
Maintained by endocrine and NS.
how does communication in the body occur? what is the exocrine system?
Chemical and electrical in the nervous system.
Hormones and neurotransmitters.
Chemical messages in the endocrine system (inside). Travels in the circulatory system.
Exocrine system involves tears, saliva and sweat (outside).
what is the positive feedback system? what are examples? is it in homeostasis?
Not found in homeostasis.
Examples are ethylene and bananas ripening- makes others ripen.
Breastmilk production- baby suckles=milk production.
Same direction as stimulus.
what is negative feedback? what is It involved in?
Very important in homeostasis as it counteracts the initial stimulus.
If the body gets hot, the body tries to cool it down.
The response is in the opposite direction of the stimulus.
what are the 5 stages of the stimulus response model?
Stimulus Receptors detect change Control centre (often the brain) Effector Response
what is the NS composed of and what is it organised into?
The nervous system is composed of highly specialised cells called neurones which are organised into: the CNS (brain and spinal cord). The PNS (extending to the rest of the body).
what do sensory, motor and interneurons do?
Sensory neurones transmit messages form receptor organs to the CNS.
Motor neurones transmit impulses from the CNS to effector organs.
Interneurones (connector neurones) relay messages between neurones.
what is information flow in the neurone?
Sensory receptor Sensory input Integration Motor output Effector
what are aspects of a neurone?
Cell body- where the nucleus is located.
Dendrites- receive signals from adjacent neutrons and conduct them towards the cell body.
Axon- transmit signals away from the cell body.
Myelin sheath- helps increase the speed of the nerve impulse.
Synapse- gap between, chemical messages, Its travel here.
what part of the NS is the FF response? what are aspects of each branch and what does it do?
Part of the autonomic NS.
Prepares the body to stay and fight or flee from a threat.
The sympathetic NS world in a stressful situation to fight or flight.
The parasympathetic NS works to relax the body and maintain homeostasis.
what does the parasympathetic NS do?
Stimulates flow of saliva Slows heart Constricts bronchi Stimulates peristalsis and secretion Stimulates release of bile Contracts bladder
what does the sympathetic NS do?
Dilates pupils Inhibits flow of saliva Accelerates heart Dilates bronchi Inhibits peristalsis and secretion Conversion of glycogen into glucose Secretion of adrenaline and noradrenaline Inhibits bladder contraction
what is the spinal reflex?
A reflex is a rapid, automatic response to a stimulus.
Minimises damage
Unconscious
Controlled by the spinal cord
what is the reflex arc? what are components of it?
Nerve pathway for reflex action. Only two neurones: sensory and motor. Receptor Sensory neurone (afferent) Integration centre (CNS) Motor neuron (efferent) Effector
