Changing the way you learn

B3.3

Interspecific Relationships
1. Mutualism
  1. Definition: occurs when both species benefit from the realtionship
  2. Examples: Small sea fish set up cleaning stations , the larger fish then come to these areas and will have their bodies cleaned of parasites. The small fish benefit as they eat the parasites and the big fish have their parasites removed.
2. Interspecific Competition
  1. Definition: non-cooperative relationship between two organisms of different species which results in both being being negatively effected at some point.
  2. Example: in animals competition for; food, water, territories, nesting sites. Always results in a decrease in the reproductive rate of the populaiton.
  3. Example: in plants competition for ; water, sunlight, space, minerals, pollinators. Influences plant growth rate per plant and results ion variation in growth of individual plants.
3. Exploitation: an "aggressive" type of behaviour that is beneficial to one and harmful to the other
  1. Herbivory
    1. Definition: is the process where by an animal eats a plant or a plant-like organism, like seaweed
  2. Predation
    1. Definition: a predator is an organism that catches and kills its prey for food
      1. Predator strategies include: belonging to a group, using snares, rapid speed, using poison to stun or kill, camouflage and lying waiting, using tools, using mimicry
      2. Prey defences include: living in groups for protection, disruptive colouration to disguise outline of body, cryptic colouration, retreating into shell, startling predator, chemical defence, curling up, confusion in large numbers, pretending to be inedible
4. Parasitism
  1. Definition: parasites exist at the expense of the host. They feed off the host without killing it. The population of parasites is density dependent as they thrive in crowded conditions.
  2. Ectoparasites: lives outside the body.
  3. Endoparasites: live inside the body
  4. Social Parasites: exploits hosts in other ways eg. cuckoos lay their eggs in others nests.
  5. Plant Parasites: compared to animals a much smaller proportions of plants are parasites, eg. mistletoe grows on other trees by connecting to the vascular tissue of the host.
Cooperative Intraspecific Relationships
1. Group Formation
  1. Advantages: easier to find a mate, easier to avoid predation because; more eyes to spot danger, defensive circles, less chance of being taken, confuse predator, protection from abiotic factors, greater learning from each other, division of labour, safer migrating as less likely to get lost and more hydro and aerodynam.ic
  2. Disadvantages: increased intraspecific competition, diseases and parasites are transferred easily due to close proximity, possible infanticide due to overthrowing male.
  3. How groups stay together
    1. Use signals such as odour, sound, visual and touch
    2. Suppressed aggression to allow mating to occur, to protect young, to reduce conflict between siblings, to maintain heirarchy
2. Mating Systems
  1. Monogamy: having only one mating partner
    1. Pair Bond
      1. Definition: a longer-lasting relationship between a particular male and female. Forms as a result of courtship =, ensures co-operative behaviour in mating and care of young, which enhances their survival chances.
    2. Advantages of monogamy: use less energy searching for a mate become experienced parents
  2. Polygamy: having multiple mating partners
    1. Advantages of polygamy: increases genetic diversity, death of a mate is not a lasting problem
  3. Polyandry: a female having more than one mating partner in a season
  4. Courtship Behaviours Include:
    1. Smell eg. pheramones
    2. Visual eg. dances, coloures markings, firefly flashes
    3. Touch eg. male spider vibrates the web to stop female spider from eating him
    4. Vocal eg. birdsong, crickets stridulating, frogs croaking
3. Parental care strategies
  1. K-strategists qualities: stable environment, large body size, long-life expectancy, high parental car, fewer offspring
    1. Advantages: usually results in successful offspring
    2. Disadvantages: uses a lot of energy to raise offspring, parental care. Cecreases liklihood of survival for parents
  2. r-strategists qualities: unstable environment, high fecundity, small body size, early maturity, short generation time, dispersed offspring
    1. Advantages: may exploit favourable environments quickly which allows them to outcompete the other species. Don't use energy over a long period of time caring for offspring
    2. Disadvantages: must use a lot of energy producing large amounts of gametes/offspring
Aggressive Intraspecific Relationships
1. Fighting
  1. Occurs due to: intraspecific competition for food, territory, mates, natural selection. young animals play fight to learn skills and slot into hierarchy. Agnostic behaviour in social animals work to avoid most fights in those close in hierarchy may fight for social position.
2. Agnostic Behaviour
  1. Definition: aggressive and submissive behaviours involved in avoiding fighting in social animals
3. Territory
  1. Definition: the area an animal will defend
    1. Advantages of maintaining a territory: only the "fittest" animals can hold a territory so only the best genes get passed onto the offspring. Ensures enough food and water for the animals that hold the territory. Reduces aggression. Ensures safe, protected nest/home for young. Reduces spread of disease and parasites. it ensures enough space for each animal, which is needed for breeding.
    2. Bounrires of territory marked by: vocalisations eg. bird song, scent markings eg. urine in dogs, visual signals eg. crabs wave claws
  2. Home range: the area an animal will search for food and nest sites.
4. Hierarchies
  1. Linear hierarchies definition: a form of animal social structure in which a linear or nearly linear ranking exists, with each animal dominant over those below it and submissive to those above it.
  2. Advantages to living in hierarchy: once hierarchy is established, there is decrease in aggressive interactions in the group. The most dominant animals, which have the 'best' genes will have the most mates. This ensures that the 'best' genes are passed onto the offspring. The most dominant animals get the best and the most food in some species the subordinate animals may get more food than if they were living indepently, as they could not bring down the kill. The subordinate animals gain protection from the dominant animals against external threats. The subordinate is mire likely to find a mate than if on it's own.
Orientation in Space
1. Tropism
  1. Definition: Growth response of a plant towards or away from stimulus coming from one direction
  3. Auxin: are plant hormones which play a role in the observed growth movements in plants called tropisms
    1. The effect of auxin on the shoots and roots depends on the concentration of auxins.
      1. low concentrations of auxin promote root growth and high concentration inhibit shoot growth and vice versa
  4. Phototropisms: is controlled by the hormone auxin which is produced in the tip of the shoot. It moves down the stem to the zone of elongation. It promotes elongation of cells in the shoot(upward growth). If light is shone on one side of the seedling it will migrate to the 'dark side'. This results in the cells on the dark side to have a greater concentration of auxin, therefor they have more elongated cells causing the shoot bend towards the source of light= positive phototropism by the shoot
  5. Geotropism: is controlled by auxin, and is the primary regulator of the of the geotropic response in plants. Geotropism is due to the different growth rates of upper and lower sides of the stem root.Therefor the auxin accumulates on the lower side of the stem or root due to gravity. High auxin in stems= cell elongation. High auxin in roots= no cell elongation.
2. Nastic Movement
  1. Definition: The movement of a plant in response to a non-directional stimulus.
  2. Example: Mimosa leaflet fold together and drop down hen touched= thigmonasty. This is a defence mechanism from animal herbivores and conserves water during windy conditions.
3. Taxis
  1. Definition: The movement of the whole organisms towards or away from a stimulus coming from one direction.
    1. Klino-taxis: moving directly towards or away from a stimulus by moving it's body side to side
    2. Tropo-taxis: moving directly toward or away from a stimulus without moving the body side to side. The stimulus is detected simultaneously by receptors on either side
    3. Telo-taxis: orientation towards a stimulus which occurs whether or not symmetrical organs are functional. There is no need for balanced messages to be recieved.
4. Kinesis
  1. Definition: The change in the rate of movement of the whole organism in response to a change in the intensity of a non-directional stimulus
    1. Orthokinesis: the speed of the movement is related to the intensity of the stimulation eg. slaters move faster under bright light to reduce the risk of dessacation
    2. Klinokinesis: the amount of random turning is related to the intensity of the stimulation eg. flatworms turn more under intense light so spend more time in darkness
5. Homing and migration
  1. Migration definition: the annual mass movement of organisms from an area where they breed to an area where they do not.
    1. Advantages: remain favourable temp., constant food supply, better breeding conditions, offspring survival improved, can reduce parasitism/spread of disease, genetic mixing.
  2. Homing definition: the ability of an organism to find its way home over unfamiliar territory.
  3. Navigation Mechanisms
    1. chemical/oflaction: involves taste or smell eg. salmon return to the stream they hatched to breed years later
    2. Visual cues: using land marks like the shape of coastlines, forests, hills eg. birds
    3. Sound: bats, dolphins, an whales use sonar to navigate.
    4. Sun compass: animal maintains a temporary fixed angle to direction of the sun to calculate direction of travel, must be able to compensate for the apparent movement of the sun so involves knowing the time of day, using an endogenous clock eg. insects,birds, fish. IF the internal biological clock is altered the normal migratory direction is altered. A disadvantage is that the sun is not always visible
    5. Star compass: used at night by nocturnal migrating birds, they recognise star patterns
    6. Moon compass: sand hoppers move towards the sea at night time using the position and use their internal clock to track this as the moon has constant movement.
    7. Earth's magnetic field compass: bees, mice and pigeons can detect the earth's magnetic field.
Orientation in Time-Rhythms
1. Biological Rhythms
  1. Circadian Rhythm: daily rhythmic activity with a period of about 24 hours(1 day),Zeitgebers are light, temperature, humidity changes
    1. Diurnal: day active eg. dogs, sparrows
    2. Nocturnal: night active eg. bats possums
    3. Crepuscular: active at dusk and dawn eg. crickets, fruit flies, rabbits
    4. Arhythmic: no regular pattern eg. animals that live in caves
  2. Circalunar Rhythm: rhythmic activity with a period of about 29 days, zeitgeber is the light of a full moon. eg. many marine species liberate gametes at certain times in the lunar cycle.
  3. Circatidal Rhythm: rhythmic activity period of about 12.4 hours(high tide to high ides) eg. fiddler crabs emerge from their burrows and feed at low tide.
  4. Circasemilunar Rhythm: rhythmic activity activity period of about 14.7 days, zeitgeber is related to spring(extra high) and neap(extra low) tides, alternating every 2 weeks. eg. whitebait spawn during spring tides in March and April
  5. Circannual Rhythm: rhythmic activity with a period of about 365 days, zeitgeber is usually photoperiodism(day length). Involves seasonal behaviour.
    1. Hibernation: winter dormancy in animals, metabolic processes slow, body temperature drops, heartrate and breathing drops, allows them to survive very cold temperatures. eg. squirrel, bear.
    2. Aestivation: dormancy in hot temperatures, common in desserts. eg. garden snail, earthworm
    3. Vernaliation: induction of flowering by a period of chilling(winter)
    4. Dormancy: seeds or underground stems reduce their metabolic rate to a minimum level during unfavourable conditions(low temp, drought). Allows survival until conditons improves
    5. Abscission: breaking off of leaves, fruits and flowers as a result of the formation of a layer of weakness at the base. Prevents water loss in winter and the plant stores proteins and minerals in the permanent tissue of the tree.
    6. Perennial: plant that flowers, seeds, flowers... year after year
    7. Biannual: plant grows in the first year, flowers and seeds in the second then dies
    8. Annual: a plant that grows, flowers, seeds in 1 year then dies
2. Biological Rhythm Terms:
  1. Exogenous Rhythms: are a direct response to the environmental cues and are not internally controlled.
  2. Endogenous Rhythms: are controlled by biological clocks. They continue in the abcense of environmental cues. However the period may change slightly from what happens in the natural envionment
  3. Zeitgeber: this is the environmental cue that resets the biological clock so that it is synchronised with the environment. Acts as a time keeper.
  4. Entrainment: This is when the internal clock is reset to take up the period
  5. Period: this is the length of one complete cycle of a rhythm. i.e. the time between the start of one activity and the start of another
  6. Free Running Period: In laboratory conditions, if all environmental cues(zeitgebers) are removed, the biological clock is a free running period.
  7. Circa: means approximately or about.The free running periods of daily, tidal, lunar and annual rhythms are not quite the same as environmental rhythms. Therefore they are called circadian, circatidal, circalunar and circannual rhythms.
3. Actograms
  1. 1. Activity is shown in the dark bars
    2. Each line represents 24 hours
  2. An actogram is a special graph that shows the activity of a plant or animal over the period of the day and many successive days.This gives a good indication of when the organism is active.
Orientation in Time-Photoperiodism
1. Photoperiodism
  1. Definition of Photoperiodism: is the regulation of seasonal activity by day length or photoperiod. eg. the production of flowers in particular seasons
  2. Long day plants: the photoperiod exceeds a certain critical day length(CDL) eg.>10hrs. The days get longer, why they flower in late spring early summer. An nights get shorter.
  3. Short day plants(long night plants): the photoperiod is less than a certain critical day legth (CDL) eg. <14.5hrs. When days are getting shorter so flower in autumn. The nights get longer, continuous darkness is important
  4. Effect of Pfr on:
    1. LDP: need minimun amount of Pfr(darkness) to promote flowering
    2. SDP: need min amount of Pr(light) to promote flowering
  5. Plants use phytochrome to detect the presence or absence of light. This detector is coupled with a biological clock with an interval timer. When the dark interval id longer than the light interval it is a short day plant. When the light interval is longer than the dark interval it is a long day plant.

Next up

B3.3

Description

Resource summary

Media attachments

Similar

	Created by hayley.dresser over 8 years ago