B4.2 Echological Niches Flashcards
niche
role played by a species in its community which includes its abiotic requirements and tolerance, and its interaction with other organism
influences growth, survival and reproduction of species and how it obtains food
what happens if 2 organisms occupy the same niche
leading to evolutionary process or competitive exclusion
where are principles of niches seen
shag and cormorant - both live and feed along coastline and rear young on cliffs and rocks but have different diets and behaviours - avoid competition from each other
shag
nest on much narrower cliffs
feeds further to sea - fish and eels
cormorants
feeds near to shore
seabed fish - flatfish
why did first organisms on earth breathe with anaerobic respiration
because the earth was less in oxygen and there was nothing to produce it
obligate aerobes examples
mycobacterium tuberculosis -TB
obligate aerobes
organisms that can only respire aerobically - all plants and animals
obligate anaerobes
organisms that only respire in the absence of oxygen
poisoned by presence of oxygen
lack defence mechanisms to protect enzymes from oxidants
obligate anaerobes examples
methane producing archaea
facultative anaerobes
organism that normally respires aerobically but has the facility to switch anaerobic respiration in the absence of oxygen
facultative anaerobes example
E. coli
lives in intestines animals and also water, food, soil
autotrophic
using external energy sources to synthesis glucose from simple inorganic substances
heterotrophic
using carbon compounds obtained from other organisms to synthesise required carbon compounds
photoautotrophs
plants that use sunlight to make food
other organisms contain pigments and are autotrophs
algae, photosynthetic bacteria, cyanobacteria
herbivores
an animal that feeds holozoically exclusively on plants
primary consumers
carnivores
flesh eating organism
secondary consumer
holozoic nutrition
nutrition in consumers where food is ingested, digested internally, absurd and assimilated
animals nutrition
get their nutrition from existing nutrients
- dependant on plant nutrition
- animal is a consumer
- animal nutrition is heterotrophic
mixotrophic
both autotrophic and heterotrophic nutrition
example of mixotropic nutrition organism
marine flatworm
- have algae living symbiotically in body
phytoplankton nutrition
take up dissolved organic carbon under inorganic nutrients stress
osmotrophy
uptake of dissolved organic material
saphrotropic
an organism that lives on or in dead organic matter, secreting digestive enzymes into it and absorbing the products of digestion
examples of saphrotrophs
fungi and bacteria
are decomposers but also carry out heterotrophic nutrition
detrivore
organism that ingests dead organic matter
holozoic nutrition
secrete enzymes and digest food outside body
archaea
domain of microbes
extremophiles
microbes in hostile environment
chemosynthesis
inorganic molecules are oxidised to release energy
energy is used to synthesise glucose
what does archaea use for energy and why
no energy so uses sunlight as energy
uses light activated ion pumps to generate ion gradients by pumping ions out of cells
energy transferred to ATP
chemoautotrophs
organisms that are chemosynthetic and use energy from chemical reactions involving the oxidation of inorganic compounds to make glucose
where are chemosynthetic archaea found
stomachs and intestines of some mammals
can also be found at the bottom of the ocean where sunlight isn’t visible
what family are humans apart of
hominidae
gorilla adaptation teeth
mainly herbivores
large masseter muscles connect skill to jaw to grind plant
temporal muscles pull up jaw - animal to bite food
sagittate crest - allow attachment for temporal muscle - forceful bit
large and developed canines and incisors
chimpanzee adaptation teeth
primarily frugivores - fruit
occasionally eat meat
less developed master and temporal muscle
what are incisors for
slicing food
what are canines for
tearing food
what are premolars and molars for
grinding food
what did humans evolve from
common ancestor with chimpanzees 4 million years ago
what do teeth explain
diets
herbivory
feeding on plants
aphids adaptations
modified piercing mouth parts called stylets - secrete pectinate to digest pectin
so it can slide between cell walls and access sucrose in phloem
how do other insects eat leaves
chewing mouth parts to bite, remove, masticate sections of leaves
examples of insects with chewing mouthparts
grasshopper, locust, cockroaches, wasps, beetle, termite, caterpillars
how do proboscis monkeys detoxifying plan toxins
bacteria in extended intestines that help in to neutralise toxins and digest cellulose
cacti adaptations to resist herbivory
spines
stinging nestles adaptations to resist herbivory
long thin hairs
contain methanol acid which causes painful sting and burning
plant adaptations to resist herbivory
modified leaves
toxic secondary compounds in seeds and leaves
deadly nightshade adaptations to resist herbivory
atropin and scopolamine in leaves, stems, berries and roots
causes paralysis in body muscles like heart
cassava roots adaptations to resist herbivory
contain cyannide
predation
interaction where one organism the predators kills and eats other organisms, its prey
predator
an organism that kills and eats other organisms
prey
organism hunted and eaten by predator
eye position of predators
eyes on front for better depth perception and binocular vision
eye position of preys
eyes on side so view of surroundings and can detect approach of predators from both sides, front and back
specialised sense organs of predators and example
all have at least one to detect prey
snakes use tongue to pock up chemicals
falcons have acute vision
speed as an advantage
for both prey and predator
prey - escape
predator - catch
cheetah onland
falcon in air
mechanical defences
hard shells on tortoises and turtles, spines of a hedgehog
physically prevent predator from eating it
camouflages
resemble background so are less visible
chameleon changes colour
mimicry and example
mimicing another predator to scare them away
example -
coral snakes - poisonous
black red and white colours which are a warning and the non poisonous snakes like king snake mimic their colours to scare off predators
toxicity
warning colours to convey that prey is toxic
caterpillar of cinnabar moth - black and yellow strips - taste unpleasant and topical chemicals
chemical defences and example
toxic chemicals a prey has to avoid predators
bombarbier beetles - hot, noxious chemicals spray from tip of abdomen
skunk - pungent liquid containing volatile sulphurous chemicals are sprayed
behavioural adaptations
not all predators rely on speed
many animals roll into a ball when threatened like woodlice and millipedes
canopy tree harvesting light
first to access sunlight
maximises photosynthesis and enables them to grow to a large size
ground layer only gets 1% of light of what canopy layer gets
lianas adaptations
woody vines - leaves and flowers in the canopy and roots in ground
use support of trees rather than a trunk
epiphytes adaptations
plants that grow on the branches of trees
seeds of these plants are deposited by birds or mammas who rest on branches of three
use support of trees
shade tolerate shrubs adaptations
contain different photosynthetic pigments from canopy plants since canopy filters out certain lights - have much larger leaves and few flowers
fundamental niche
potential extent of a species based on adaptations and tolerance limits
where an organism could live
realised niche
actual extent of a species when in competition with other species
where an organism does live
