Transcript heterotrophs

Third lecture
Ecosystem
An ecosystem is a self-sustaining, dynamic
community of plants and animals in
relation to their physical environment.
System
Interacting parts that share common
location in space, time and/or function
Ecosystem
• All of the organisms living in a particular
place as well as the chemical/physical
factors with which they interact.
• Range in size from small (like aquarium)
to large (like forest)
• E.g. desert ecosystem: organisms that
live there (cacti, snakes, rodents), soil
chemistry, average rainfall, temperatures
etc.
Any ecosystem is composed of:
1-Abiotic components (nonliving factors)
such as: light, temperature, water,
oxygen, minerals, pH and soil.
2-Biotic components (living things) such as:
i-Producers (autotrohps): they are the
green plants since they produce organic
compounds that serve as food.
Autotrophs
A groups of organisms that can use the energy in sunlight
to convert water and carbon dioxide into Glucose (food)
Ex. Plants and Algae
Autotrophs
• Chemotrophs
– Autotrophs that get their energy from inorganic
substances, such as salt
– Live deep down in the ocean where there is no
sunlight
– Ex. Bacteria and Deep Sea Worms
ii-Consumers (heterotrophs):
Organisms that do not make their own food:
• Primary consumers (herbivores): Organisms
that feed directly on green plants.
• Secondary consumers: Are carnivores that prey
on the primary consumers.
• Tertiary consumers: Predators on the
secondary consumers and primary consumers.
• detritivores -consumers that get their energy
from detritus-nonliving organic material.
iii-Decomposers:
• These organisms decompose organic
material in ecosystem and transfer
chemical elements in inorganic forms to
reservoirs such as soil, water, and air.
• These chemical elements are cycled, or
returned to the environment, where
other living things use them again.
Consumers (heterotrophs)
They consume other organisms
in order to live
Ex. Rabbits, Deer, Mushrooms
Heterotrophs
1.Scavengers/Detritivores: feed on the tissue
of dead organisms (both plans and animals).
Ex. Vultures, Crows, and Shrimp
Heterotrophs
2.Herbivores: eat only plants
Ex. Cows, Elephants, Giraffes
Heterotrophs
3.Carnivores: eat only meat
Ex. Lions, Tigers, Sharks
Heterotrophs
4.Omnivores: eat both plants and animals.
Ex. Bears and Humans
Heterotrophs
5.Decomposers: absorb any dead material
and break it down into simple nutrients or
fertilizers. Ex. Bacteria and Mushrooms