TOPIC 1:CLASSIFICATION KINGDOM FUNGI
FOOD
CHAINS- a food chain is a linear
relationship among the organisms of a community in which each organism feeds on
the one preceding it.
- It presents energy flow from one trophic level to the next.
- Each organism feeds on therefore derives energy from the proceedings one in return it is eaten by and therefore provides energy for the one following it.
- The arrows indicate the direction of energy flow
Example of
food chain:
FOOD WEBS
A food web refers to the several
food chains interlinking together
- Most herbivores consume more than one kind of plants and omnivores consume more than one kind of plant and animal and the decomposer consume more than one kind of herbivore
SIGNIFICANT OF FOOD CHAINS AND FOOD
WEBS
i) Food chains and food webs
facilitate the flow of energy in the environment.
ii) Helps to maintain the balance of
the total numbers of organisms in the environment
TRANSPORTATION OF MATERIALS
Introduction
The basic characteristics of all
living things are nutrition, respiration, excretion, growth and development,
movement, reproduction and sensitivity. In order for these life processes to
take place, there must be transportation of materials. Materials are
transported either from the environment into the organism or from one part of
the organism to another. They can also be transported from the organism into
the environment.
For example, during nutrition,
organisms take in food substances that they need to provide them with energy.
The food must also be transported to all parts of the organism. Respiration
requires oxygen, which must be taken in from the environment. During excretion,
waste materials from the organism are transported to the excretory organs and
removed from the body. Growth requires the production and transportation of
growth hormones to the growing parts of the organism. Movement and locomotion
are made possible by the transportation of impulses to the relevant organs.
Reproduction requires the movement of gametes (sex cells) or the transportation
of genetic material. Sensitivity is made possible by the transportation of
messages about the presence of a certain thing in the environment.
Transportation is therefore very
important for the survival of living things.
