B4.2 Ecological niches

Define the term niche?

The role of a species within its habitat

Give me 5 factors that make up an organism’s niche:

What it eats

Which other species depend on it for food

What time of day it is active

Exactly where in a habitat it lives

Exactly where in a habitat it feeds

 

What are examples of biotic interactions that influence an organisms availability to fill its niche? 4

Contact with pathogens and parasites

Competition for food

Avoiding predators

Finding food

Where can obligate anaerobes be found? 3

Lower layers of soil

Deep water

Inside the bodies of other organisms

What are facultative anaerobes?

Organisms that mainly respire aerobically but can switch to anaerobic respiration in the absence of oxygen without negative effects.

What are obligate aerobes?

Organisms that cannot survive in the absence of oxygen and rely on aerobic respiration to release energy from food.

What is the Abiotic component of an ecological niche

The habitat in which an organism lives and the resources within the environment

What is the Biotic component of an ecological niche

The activity patterns of the organism and its interactions with other species

What is competitive exclusion

One species uses the resources more efficiently, driving the other species to local extinction

What is Resource partitioning

Both species alter their use of the habitat to divide resources between them (niche separation)

What is a fundamental niche

the entire set of conditions under which an organism can survive and reproduce

What is a realised niche

the set of conditions used by an organism after including interactions with other species

What happens if obligate aerobes perform anaerobic respiration?

They need to quickly switch to aerobic respiration or it will damage their effects on cells.

Define the term holozoic nutrition?

organic matter is ingested and then digested internally, before being absorbed and assimilated

What’s heterotrophic?

An organisms that gain their organic molecules from the tissues of other organisms.

 

What is a mixotroph?

An organism that can use both autotrophic and heterotrophic methods of nutrition.

What does Autotrophic nutrition?

involves synthesising organic molecules from simple inorganic substances

What does Heterotrophic nutrition?

involves obtaining organic molecules from other organisms (either living material or non-living remains)

What is an Archaea?

Metabolically diverse group of organisms capable of performing a variety of modes of nutrition

What are Consumers in holozoic nutrition?

Organisms that feed on living or recently killed organisms

What are Scavengers in holozoic nutrition?

Organisms that feed on dead and decaying carcasses rather than hunting live prey

What are Detritivores in holozoic nutrition?

organisms that feed on non-living organic matter – such as detritus and leaf litter

What is saprotrophic nutrition:

organisms that live on (or in) non-living organic matter and secrete digestive enzymes to break the material down externally

What are saprotrophs referred to?

As decomposers

Give me two examples of decomposers?

Bacteria and fungi

What are Herbivores?

a type of heterotrophic consumer that feed principally on plant matter

What are two defences that plants have developed to resist herbivores?

Physical structures and Chemical compounds

What are 4 adaptations of herbivores to overcome the defences of plants?

Specialised mouthparts, Digestive systems, Microbiotic bacteria and Metabolic processes.

What are carnivores?

a type of heterotrophic consumer that feed primarily on animal matter (i.e. meat eaters)

What are four adaptations that predators have developed to catch their prey?

Physical structures, Appearances, Chemical compounds, Behaviours

What are 4 characteristics preys possess to resist predators?

Physical structures, Appearances, Chemical compounds, behaviours

What are Omnivores?

a type of heterotrophic consumer that feed on both plant and animal matter 

What characteristics do Hominids (Apes) have related with their teeth.

Have narrower jaws and smaller teeth for chewing softer animal tissue.

How have teeth changed for humans?

Jaws have become narrower, with smaller teeth, as humans developed tools and hunting practices to support greater meat-eating behaviours