B4.2 Ecological Niches

What is the name of the unique role a species plays in an ecosystem?

An ecological niche

What are the factors determining ecological niches?

Biotic and abiotic

What determines where a species live in an ecosystem?

Zone of tolerance

What are the two names of species determined on the way they take in food

Autotrophic and heterotrophic

Where does autotrophic species get their energy from?

Using an energy source for synthesis

Where does heterotrophic species get their energy from?

taking food by ingesting other organisms

What are the names of the three types of species in relation to oxygen?

Obligate aerobes, obligate anaerobes, and facultative anaerobes

What are the requirements for obligate aerobes?

Always need oxygen

What are the requirements for obligate anerobes?

No oxygen as it kills the organism

What are the requirements for facultative anaerobes?

oxygen used if available but survives anoxi conditions

Give an example of an obligate aerobe?

All plants and animal

Give two examples of obligate anaerobes

Methanogenic archaea and tetanus bacteria

Give two examples of facultative anaerobes

Yeast and e. coli

What is photosynthesis used for?

Fixing CO₂ and making carbon compounds

What are the three groups of organisms that use photosynthesis?

Plants, eularyotic algae and caynobacteria

How do animals obtain amino acids and carbon compounds?

By taking in food

Wha is the name given to the way in which humans consume food?

Holozoic nutritiun

What are the 5 events composing holozoic nutrition?

1. ingestion

2. digestion

3. absorption

4. Assimilation

5. egestion

Give an example of ingestion

Taking food into the gut

Give an example of digestion

Breaking large food molecules into smaller ones

Give an example of absorption

Transporting food accriss the plasma membrane into the blood

Give an example of assismilation

Using digested food to synthesise proteins

Give an example of egestion

removing undigested material from the end of the gut

What is the name of the organisms that are neither autotrophic or heterotrophic?

Mixotrophic

Which groups of organisms are mostly mixotrophic?

Protists (unicellular eukaryotes)

What is the name given to organisms that can either be entirely autotrophic, entirely heterotrophic, or use both?

Facultative mixotrophs

What are the two ways in which euglena gracilis consumes energy?

Photosynthesis and endocytosis

Give an example of a facultative mixotroph

Euglena gracilis

What are organisms which feed off dead organic matter?

Saprotrophs

How do saprotrophs digest food?

Externally

What does a saprotroph do to digest externally?

Secretes enzymes

What enzyme is used to digest protein in amino acids?

Protease

How does the externally digested food enter the saprotroph?

Diffusion via the plasma membrane

What is the more common name for saprotrophs?

Decomposers

In what way are archaea diverq?

In their source of energy for ATP production

What are the three types of archaea?

1. Chemoheterotrophs

2. Photoheterotrophs

3. Chemoautotrophs

How do chemoheterotrophs get energy for ATP production?

Oxidation of carbon coumpounds from other organisms

How do photoheterotrophs get energy for ATP production?

Absorption of light using pigments

How do chemoautotrophs get energy for ATP production?

Oxidation of inorganic molecules

Give an example of an oxidation of inorganic chemicals for the attainment of energy for ATP production on chemoautotrophs

Fe²⁺ ion to Fe³⁺

How do chemoheterotrophs obtain carbon compounds?

From other organisms

How do photoheterotrophs obtain carbon compounds?

From other organisms

How do chemoautotrophs obtain carbon compounds?

synthesised from CO₂ by anabolic reactions

Describe the general shape of herbivore teeth

large and flat

Why are herbivore teeth large and flat?

To grind down fibrous plant tissue

Describe the general shape of omnivore teeth

mix of types

Wy are omnivore teeth a mix of different types of teeth?

As they eat both meat and plants

Describe the general shape of carnivore teeth

Pointy

What teeth do humans use to crush and grind food?

flat molars

What teeth humans have to tear through tough foods like meat?

Sharp canines and incisors

Describe the mouth and teeth of inseacts that feed on leaves

Jaw-like mouthparts and mandibles

Describe the mouth and teeth of inseacts that feed on phloem sap

Sharp, tubular mouthparts

Describe the mouth and teeth of inseacts that feed on nectar

Long, tubular mouthparts

Why do insects that feed on leaves jave jaw-like mouthparts and tough mandibles?

To pite off, chew and ingest leaves

Why do insects that feed on phloem sap have sharp, tubular mouthparts?

To pierce leaves or stems to reach phloem tubes

Why do insects that feed on nectar have long, tubular mouthparts?

To reach nectary flowers

What are three adaptations that plants have developed to deter herbivore attacks?

1. Sharp spines (e.g. rose thorn)

2. Stings (e.g. stinging nettles)

3. Store toxic secondary metabolites

Where are the two most likely places secondary metabolites are stores?

Seeds and leaves

Give a structural adaptation for predators

Large pointy teeth in vampires to such blood

Give a structural adaptation for predators

Venom containing toxins to paralyse prey

Give a behavioural adaptation for predators

Waving luminescent fin rays to attrack prey

Give a structural adaptation for prey

Shells on mollusc body’s to protect them

Give a chemical adaptation for prey

Accumulation for toxins

Give a behavioural adaptation for prey

Swimming in schoals

Give an example of a strategy an average tree uses to obtain light

Dominant leading shoot rows rapidly

Give an example of a strategy a Liana uses to obtain light

Climb other trees, use them for support so need less xylem tissue

Give an example of a strategy an epiphyte uses to obtain light

Grows on trunks and branches of other trees to go high up

Describe how strangler epiphytes obtain light

Grow up a tree trunk, encircles it, grows leaves shading the tree they climbed and killing it

What is the name given to the area that a species will grow if it was living without any competition?

A fundamental niche

What is the name given to the area of the fundamental niche which a species actually grows when living with competitors?

A realised niche

Can two species have the same fundamental niche?

Yes

Can two species have the same realised niche?

No

What happens if species A entirely outcompetes species B in a fundamental niche?

Species B is excluded from the ecosystem

In terms of niches, what must each species have in order to survive?

A realised niche which differes from those of all other species