BIOLOGY
Chapter 1:
Characteristics and classification
of living organisms
produced by:
,WHAT ARE THE CHARACTERISTICS OF LIFE?
Cells
All organisms are made up of simple units called CELLS. The cells of an organisms
carry out activities necessary for the organism to stay alive. A cell is a unit of life
Nutrition
Living organisms need energy to stay alive. They also need nutrient molecules to
make the living matter in cells
Nutrition is the TAKING IN of materials for ENERGY, GROWTH and
DEVELOPMENT
The basic difference between plants and animals is how they carry out nutrition
Plants take in raw materials (CARBON DIOXIDE and WATER) to make food
through PHOTOSYNTHESIS
Animals cannot make their own food. They have to feed on plants or other
animals to survive, grow and carry out their daily activities
Respiration
Many chemical activities occur in the cells of living organisms. These are called
METABOLIC activities or METABOLISM. Energy is required for metabolic and
other activities such as GROWTH and DEVELOPMENT
Living organisms obtain energy through RESPIRATION
Energy is released when nutrient molecule such as glucose are broken down
during respiration
RESPIRATION is the breakdown of nutrient molecules in cells to release energy
for METABOLISM
Excretion
Metabolic activities may produce substances that can be harmful if they
accumulate in the body. These waste products and excess substances must be
removed.
EXCRETION is the removal of METABOLIC WASTE products and substances in
excess of the body’s requirements
,WHAT ARE THE CHARACTERISTICS OF LIFE?
Growth and Development
GROWTH is the PERMANENT increase in DRY MASS and size of an organism
When absorbed food is converted into living matter in the cells of an organism,
some of the new matter formed is used to repair worn-out parts of the cells. The
rest is added to the original living matter
This increases the SIZE of the individual cells. As living organisms grow, their cells
also DIVIDE to form more cells, making the body larger
Living organisms grow as well as DEVELOP. Development may make an organism
become more COMPLEX and CHANGE IN FORM
Movement
MOVEMENT is an action by an organism or a part of an organism, causing it to
change its POSITION or PLACE
Reproduction
REPRODUCTION is the process that makes more of the same kind of organism.
Sensitivity
SENSITIVITY is the ability of an organism to DETECT and RESPOND to CHANGES
in the EXTERNAL and INTERNAL environment
WHAT ARE THE DIFFERENCES BETWEEN A LIVING
ORGANISM AND NON-LIVING MATTER?
Some of the characteristics of living organisms can be found in certain non-living
matter
For example, a motorcar can move and give off waster products when its fuel is burnt.
It also has a well-organised and complex structure. However, machines cannot
reproduce and they cannot grow.
ALL characteristics of life must be considered when distinguishing between a living
organism and non-living matter
, THE BIOLOGICAL SYSTEM OF CLASSIFICATION
In the biological system of classification, living organisms are classified according to a
GRADED SCALE or HIERARCHY
As we go down the hierarchy, the resemblance between organisms becomes much
closer
Organisms are first divided into KINGDOMS, such as
KINGDOM
the plant kingdom and the animal kingdom
Within each kingdom, organisms are further classified
PHYLUM
into several PHYLA (singular: phylum)
CLASS A phylum is made up of several CLASSES
ORDER Each class is made up of ORDERS
Each order is made up of families. Within each family,
FAMILY the organisms resemble one another fairly closely
Each family consists of a varying number of GENERA
GENUS (singular: genus)
A genus has usually several species. A SPECIES is a
SPECIES group of organisms that can breed with one another
to produce fertile offspring
HOW DO WE NAME A SPECIES?
Carolus Linnaeus used Latin to give two names to each species
This naming system is called the BINOMIAL SYSTEM OF NAMING SPECIES
It is an internationally agreed system
The first name refers to the GENUS to which the organism belongs. It also starts
with a capital letter
The second name is the SPECIES name. It starts with a small letter
Both the genus and the species names are either ITALICISED or UNDERLINED
Chapter 1:
Characteristics and classification
of living organisms
produced by:
,WHAT ARE THE CHARACTERISTICS OF LIFE?
Cells
All organisms are made up of simple units called CELLS. The cells of an organisms
carry out activities necessary for the organism to stay alive. A cell is a unit of life
Nutrition
Living organisms need energy to stay alive. They also need nutrient molecules to
make the living matter in cells
Nutrition is the TAKING IN of materials for ENERGY, GROWTH and
DEVELOPMENT
The basic difference between plants and animals is how they carry out nutrition
Plants take in raw materials (CARBON DIOXIDE and WATER) to make food
through PHOTOSYNTHESIS
Animals cannot make their own food. They have to feed on plants or other
animals to survive, grow and carry out their daily activities
Respiration
Many chemical activities occur in the cells of living organisms. These are called
METABOLIC activities or METABOLISM. Energy is required for metabolic and
other activities such as GROWTH and DEVELOPMENT
Living organisms obtain energy through RESPIRATION
Energy is released when nutrient molecule such as glucose are broken down
during respiration
RESPIRATION is the breakdown of nutrient molecules in cells to release energy
for METABOLISM
Excretion
Metabolic activities may produce substances that can be harmful if they
accumulate in the body. These waste products and excess substances must be
removed.
EXCRETION is the removal of METABOLIC WASTE products and substances in
excess of the body’s requirements
,WHAT ARE THE CHARACTERISTICS OF LIFE?
Growth and Development
GROWTH is the PERMANENT increase in DRY MASS and size of an organism
When absorbed food is converted into living matter in the cells of an organism,
some of the new matter formed is used to repair worn-out parts of the cells. The
rest is added to the original living matter
This increases the SIZE of the individual cells. As living organisms grow, their cells
also DIVIDE to form more cells, making the body larger
Living organisms grow as well as DEVELOP. Development may make an organism
become more COMPLEX and CHANGE IN FORM
Movement
MOVEMENT is an action by an organism or a part of an organism, causing it to
change its POSITION or PLACE
Reproduction
REPRODUCTION is the process that makes more of the same kind of organism.
Sensitivity
SENSITIVITY is the ability of an organism to DETECT and RESPOND to CHANGES
in the EXTERNAL and INTERNAL environment
WHAT ARE THE DIFFERENCES BETWEEN A LIVING
ORGANISM AND NON-LIVING MATTER?
Some of the characteristics of living organisms can be found in certain non-living
matter
For example, a motorcar can move and give off waster products when its fuel is burnt.
It also has a well-organised and complex structure. However, machines cannot
reproduce and they cannot grow.
ALL characteristics of life must be considered when distinguishing between a living
organism and non-living matter
, THE BIOLOGICAL SYSTEM OF CLASSIFICATION
In the biological system of classification, living organisms are classified according to a
GRADED SCALE or HIERARCHY
As we go down the hierarchy, the resemblance between organisms becomes much
closer
Organisms are first divided into KINGDOMS, such as
KINGDOM
the plant kingdom and the animal kingdom
Within each kingdom, organisms are further classified
PHYLUM
into several PHYLA (singular: phylum)
CLASS A phylum is made up of several CLASSES
ORDER Each class is made up of ORDERS
Each order is made up of families. Within each family,
FAMILY the organisms resemble one another fairly closely
Each family consists of a varying number of GENERA
GENUS (singular: genus)
A genus has usually several species. A SPECIES is a
SPECIES group of organisms that can breed with one another
to produce fertile offspring
HOW DO WE NAME A SPECIES?
Carolus Linnaeus used Latin to give two names to each species
This naming system is called the BINOMIAL SYSTEM OF NAMING SPECIES
It is an internationally agreed system
The first name refers to the GENUS to which the organism belongs. It also starts
with a capital letter
The second name is the SPECIES name. It starts with a small letter
Both the genus and the species names are either ITALICISED or UNDERLINED
