ENVIRONMENTS

Read 199-207

SIZES OF ENVIRONMENTS

SMALLEST

LARGEST

ORGANISM MICRO-HABITAT HABITAT BIOME BIOGRAPHICAL REGION BIOSPHERE

ECOSYSTEMS BIOTIC – living ABIOTIC – (A)non-living Examples:

Abiotic factors that influence tolerance (worksheet)

BIOTIC ABIOTIC

COMPARISONSFACTORS AQUATIC HABITAT TERRESTRIAL HABITAT

Water availabilityDissolved mineralsTemperatureLightBuoyancy/DensityViscosity (resistence to movement)

Gas availabilityPressure

COMPARISONSFACTORS AQUATIC HABITAT TERRESTRIAL HABITATWater availability

Readily available Varies in availabilitySpecies have special features to transport it

Dissolved minerals

Ions in waterFresh water – low soluteSalt water – high solute

Ions in soilVariable in amounts

Temperature Less variation Greater variationLight Limited – depends on

clarityReadily available

Buoyancy/Density

More dense = more support

Less dense = less support

Viscosity (resistence to movement)

Very viscose Not very viscose

Gas availability O2 not readily availableCO2 readily available

O2 readily availableCO2 not readily available

Pressure Increases with depth Descreases with altitude

ECOLOGICAL NICHE An ecological niche describes how an

organism or population responds to the distribution of resources and competitors . The way of life of a species.

The optimum range refers to the abiotic factors at which the organisms functions best.

Physiological stress refers to outside the preferred niche/optimum range.

Looking at niches (worksheet)

PLANTS & TROPISMS

Read 219-228

TROPISMS Tropism is the directional growth response of a

plant to an environmental stimulus. Positive tropism – growing toward a stimulus Negative tropism – growing away from a

stimulus Complete the table:Tropism Stimulus ResponsePhototropismGeotropismHydrotropismThigmotropismChemotropism

TROPISMS

Tropisms (worksheet) Leaves can tell a story (worksheet)

Tropism Stimulus ResponsePhototropism Light Positive: shoots grow towards the

lightNegative: roots (if responsive) grow away

Geotropism Gravity Positive: roots grow downwardsNegative: shoots grow upwards

Hydrotropism Water Roots grow towards waterThigmotropism Touch,

contactStems and tendrils grow round or against points of contact with solid objects (eg other plants)

Chemotropism Chemicals Positive: pollen tubes of some plants are attracted to the stigma of same species, enabling fertilisation. Ovary releases chemicals to produce response.

PLANTS IN DIFFERENT ENVIRONMENTSCategory Description CharacteristicsHydrophytes

Aquatic plants: floating or living in water

Have little or no cuticle on stems and leaves. Stomata (specialised pores for gas exchange) are found on the upper surface of the leaves. Small amount of transport tissue (xylem).

Xerophytes

Dry conditions Fleshy, succulent plants OR hard-leaved sclerophylls. Thick waxy cuticle, hair covering leaves, few stomata, reduced leaf surface area, leaf orientation away from sun.

Halophytes

Salt tolerant Many are succulents. Usually have high osmotic pressure in cytoplasm, control salt levels in shoots. If excess salt enters via the leaves they cannot control osmotic concentration so stomata close reducing transpiration and CO2 uptake.

Mesophytes

Moist conditions Perennials – survive underground as bulbs, tubers. Annuals survive with dormant seeds. Stomata control water loss.

Epiphytes Aerial: growing on branches or trunks.

Not parasitic.

Which is which?

Know the definitions of these:

Epicormic bud Lignotubers Phytohormones Gibberellins Cytokinins Abscisic acid Ethylene Auxins

Life of Plants (video)

Phytochromes Photoperiodism Dormancy Taxis Nastic Nutation

ANIMAL ADAPTATIONS

ADAPTATIONS Adaptations an organism has enables it to

compete successfully to obtain its requirements, often in changing conditions.

These can be: Structural Physiological Behavioural Reproductive

Adaptations (worksheet)

STRUCTURAL ADAPTATIONS

Life of Mammals (video)

PHYSIOLOGICAL ADAPTATIONS

Read 233-267

MAINTAINING BALANCE Organisms (that are subject to extreme

conditions) have particular strategies and mechanisms that ensure relatively stable internal conditions – conditions that are necessary for biochemical process in cells to be maintained – despite what is happening in the external and internal environments.

Internal environment = the fluid surrounding living cells within a multi-cellular organism.

HOMEOSTASIS is the maintenance of a relatively stable internal environment, within narrow limits

EXAMPLES: Blood sugar (Glucose concentration in the

blood) approximately 0.1%

Blood pH approximately 7.4

Blood pressure approximately 120 / 80

Body temperature approximately 37°C (98.6°F)

Homeostasis involves most/all organs and systems of the body but especially Nervous system Hormone (endocrine) systems.

Factors that can interfere with homeostasis include: Extremes in the external environment Disease Trauma Inherited disorders High levels of toxic substances

Stimulus

(input)

Response

(output)

RECEPTOR

EFFECTOR

COORDINATION CENTER

Cancels or

counteracts the original stimulus

FEEDBACK MECHANISMS: Minor fluctuations occur, but signals about these disturbances are fed to a control centre which interprets what is going on.

NEGATIVE FEEDBACK: Results in returning the changed internal conditions back to its optimal level.

Stimulus - Response Model:

NERVOUS SYSTEM &

ENDOCRINE SYSTEM

PAMPHLET

PART ONE NERVES & HORMONES TOGETHER...

TEMPERATURE REGULATION

TEMPERATURE REGULATION

Ectothermic: organisms whose body temperature is governed by an _________ heat source.

Endothermic: organisms whose body heat is generated from _________ metabolic sources.

Poikilothermic: Refers to an organism having a body temperature that can vary greatly with changes in the external environment.

Homeothermic: Refers to an organism that is able to maintain an internal body temperature within narrow limits.

Organisms gain heat from their environment but they also lose heat to the environment. There are several mechanisms involved in the gain or loss of heat.Mechanism Description (page 254)

RadiationConductionConvectionEvaporation

Animals have structural, physiological and behavioural adaptations, which equip them with heat gain and loss.Types of

AdaptationsExamples Description

Structural Fur, feathers, blubberLarge ears

Behavioural Retreating to a burrow, moving in the shadeHuddling with others, curling up

Physiological Shivering, increase metabolismConstriction of blood vessels to skinPiloerectionDilation of blood vessels to skinSweating

PART TWONERVES & HORMONES TOGETHER... OSMOREGULATION

PROVIDE A DEFINITION PROVIDE 4 DIFFERENT EXAMPLES

BEHAVIOURAL ADAPTATIONS

Read 271-290

The scientific study of the behaviour of animals is called ethology.

The behaviour of an animal describes what it does, how it acts or reacts to a particular situation.

Question: HOW does an animal know how to behave, act or

react in a particular situation?

INNATE BEHAVIOUR Or instinct, can be thought of as internal

“programming” which all animals have depending on the type of animal they are.

This type of behaviour does not have to be learnt because it is inborn (genetically controlled).

Include: Rhythmic Group Organisation Communication Reproductive Territorial Behaviour Aggressive Behaviour

Rhythmic Repeating behaviours at regular intervalsType Definition Examples Survival Value

Circadian rhythms:DiurnalCircadian rhythms:NocturnalCircadian rhythms:CrepuscularMigration

Feeding

Group Organisation Forming groups within animal species

increases their chance of survival.Type Explanation Examples Benefit to the

groupSuccessful cooperation

Working together

Wanting some alone time

Communication Will be through one of three kinds: acoustic,

chemical or visual.Species Means/Method Survival ValueTermite

Lyrebird

Whales

Lemurs

Baboon

Reproductive, Territorial & Aggressive Reproductive:

Enables individuals to locate a member of their own species, mate, reproduce and care for their young.

Courtship rituals and mating calls increase chances of finding a mate. Can included visual communication (eg. brightly coloured plumage in birds)

Grooming establishes bonds. Helps with hygiene, and the parasites offer a good source of protein when eaten.

Territorial: Marking and defending their home range allows animal to

protect its resources including food, shelter and potential mates.

Aggressive: Often displayed to establish hierarchy within a group.

LEARNED BEHAVIOUR Learning begins as soon as the animal is

exposed to the outside world. Animals change their behaviour as a result of

experiences that require them to do so. As the animal grows, it constantly adapts and

adjusts it’s behaviour to respond to it’s environment.

Behaviour Explanation Examples

Classical Conditioning

Operant Conditioning

Habituation

Insight

Imprinting

Observational

Trial and error

REPRODUCTIVE ADAPTATIONS

Read 291-297

Write definitions and notes on the following reproductive adaptations: Courtship: Parenting behaviour: Development and life cycles:

Insects Monotremes Marsupials Placentals