TOPIC 1:CLASSIFICATION KINGDOM FUNGI
THE
COMMONS TERMS IN STUDYING THE NATURAL ENVIRONMENT
BIOTIC
FACTORS: Are all the living components of
the environment. They are plants, animals and micro – organisms
ABIOTIC
FACTORS: Are the non – living components of
the environment e.g. light, water, rocks and soil.
ECOLOGY
– Is the branch of biology that deals with the study of the relationship
between living thing and their natural environment
POPULATION
– Is the total number of a certain species of organisms in a community.
Example; number of frogs in a pond
COMMUNITY
– This refers to the populations of different organisms living in a specific
area called a habitat. Example a grass land community could include
grass, acacia trees, lions, antelope, giraffe and cheetah.
HABITAT
– Is a specific area with a specific set of conditions that is appropriate for
a certain community and where the community ties or it is the home of living
organisms. Example; tropical rain forest, a desert, a swamp, a pond, a
grassland and ocean
ECOSYSTEM
– This is a natural unit made up of living and non – living thing whose
interactions lead to a self – sustaining system
- An ecosystem is made up of communities.
BIOTIC
FACTORS
Biotic
factors are the living components in the environment. They can either be
population factors or community factors.
1. POPULATION
FACTORS – This include:
i)
Population density – The number of organisms in a given area
ii)
Dispersion – the geographical distribution of organism in an area
iii) Age structure
– the distribution of population according to age
iv) The
ratio of males to female
v) The
number of births
vi) The
number of deaths
vii)
Population growth – The rate of/at which the number of organism is increasing
2. COMMUNITY
FACTORS – This includes food chains and food webs,
- These
are feeding relationships that represent that represent flow of energy and
recycling of nutrients in a community.
ABIOTIC
FACTORS
These are
non – living components of the environment. They can be climatic, soil or
geological.
CLIMATIC
FACTORS
1. Temperature;
is the degree of heat in a place
-
Organisms adapt to the temperature in their habitats in various ways.
Example
some plants shed their leaves or roll them when it is very hot so as to avoid
excessive loss of water
- Animal
in very cold place has extra fat for insulation
2. Light:
it is obtained from the sun
- It
affects opening of stomata
- It is
important during photosynthesis
Example
some animal hunt in bright daylight (e.g. hawks) while others hunt at dark or
dawn when there is dim light (e.g. lions) and others hunt at night (e.g. owls
and bats)
3. Wind:
It increases threat of water evaporation from water bodies as well as for
living organism
- Wind is
important in the formation of rain and the disposal of some plant seed.
4. Atmospheric
pressure: when atmosphere pressure is high concentration of oxygen and
carbon dioxide are high so as threaten of gaseous exchange and respiration is
high. The opposite is also true. This affects the distribution of both plants
and animal
5. Water
serves as habitat for a large variety of organism. Water serves as solvent
a medium of transportation and a temperature regulatory.
AQUATIC
FACTORS
These are
factors that affect water bodies and life in water
- Salinity: This is the quantity of salts dissolved in water.
- Aquatic plants have roots that
absorb minerals salts and water depending on the concentration in the plant
cells
- Some aquatic organisms are adapted
to living in fresh water habitat while others live in salt water habitants.
2. WAVE ACTION: It is
important for organism to live in artificial zone. These organism are covered
by water during high tide and low tide
- Such organism includes shrines
different types of sea weeds, crabs and clams.
SOIL FACTORS
1. Soil texture – this refers to the
size of soil particles.
- Soil texture affects drainage of
the soil, fertility and distribution of plants.
2. Soil composition: This is the
proportion of components of soil including mineral salts, Air and micro –
organism, water and remains of living things
- These components affect soil
fertility and hence plant growth.
3. SOIL PH: This is the degree of
acidity or alkalinity of soil
- Different types of plants grow
into soil with different PH value. Example; tomato and pineapple growth in
slight acidic soil while onions and cabbage prefer slightly alkaline soil
GEOLOGICAL FACTORS
- These are factors concerned with the features of the land surface.
(i) ALTITUDE – Is the height above
sea level
- At high altitudes, atmospheric
pressure, temperature and oxygen concentration are lower while the rain fall
are higher compared to low attitude. This affects distribution of both plants
and animal.
(ii) GEOLOGICAL SUBSTRATUM – refers
to the various types of rocks that disintegrate to form the soil in an area.
The chemical composition of the rocks is reflected in the chemical composition
of the soil, this determine soil PH and fertility.
(iii)SLOPE – refers to gradient of
land slope, can be steep, moderate or gentle. Soil erosion is highest in steep
slopes and lowest in gentle slope, soil erosion removes top soil making the
soil less fertile. This interferes with plant growth.
Interaction of living and non-living
things
The interaction of biotic and
abiotic components "of the environment is important for the completion
-natural cycles such as the water cycle, the carbon cycle and the nitrogen
cycle.
The water cycle
Water cycle refers to how water
circulates in the environment. Movement of water in the environment occurs as
shown in the figure below:
Interaction of living and non-living
things
The interaction of biotic and
abiotic components "of the environment is important for the completion
-natural cycles such as the water cycle, the carbon cycle and the nitrogen
cycle.
The water cycle
Water cycle refers to how water
circulates in the environment. Movement of water in the environment occurs as
shown in the figure below:
In the water cycle:
(i) Groundwater and run-off (water
from rain) flow into streams and rivers,
(ii) The streams and rivers flow
into lakes and oceans
(iii) Water evaporates into the
atmosphere from water bodies such as oceans and lakes and from plants through
transpiration
(iv)The evaporated water
precipitates to form water vapor. Water vapor condenses to form clouds
(v) Wind causes clouds to move, for
example from above the ocean to above the land.
(vi) Rain falls and is absorbed by
plants or forms groundwater and run-off. The cycle thus begins again.
Forests act as water catchment areas
and prevent excess loss of water from the land. Wetlands, such as swamps and
marshes, help to control flooding and are also important for water
purification.
Thecarboncycle
Carbon cycle refers to a biochemical cycle in
the environment where by carbon dioxide is taken up from the atmosphere and
incorporated into the plant tissues during photosynthesis
>>>>>>>>>>>>>>Inaendelea>>>>>>>>>>>>>>>>>>>>
