Chp 1 - Characteristics and Classification of Living Organisms

What is an organism

A living thing.

What are the characteristics of living organisms

MRS.GREN -
Movement, Respiration, Sensitivity, Growth, Reproduction, Excretion, Nutrition.

Describe the characteristic - Movement

Movement: an action by an organism or part of an organism causing a change of position or place.

Describe the characteristic - Respiration

Respiration: the chemical reactions in cells that break down nutrient molecules and release energy for metabolism.

Describe the characteristic - Sensitivity

Sensitivity: the ability to detect and respond to changes in the internal or external environment.

Describe the characteristic - Growth

Growth: a permanent increase in size and dry mass.

Describe the characteristic - Reproduction

Reproduction: the processes that make more of the same kind of organism

Describe the characteristic - Excretion

Excretion: the removal of the waste products of metabolism and substances in excess of requirements.

Describe the characteristic - Nutrition

Nutrition: the taking in of materials for energy, growth, and development

What is metabolism?

The chemical reactions that take place in living organisms.

What is dry mass?

The mass of an organism after it has been killed and all water removed from it.

What are common ancestors?

A species that lived in the past and is thought to have given rise to several different species alive today; for example, all mammals share a common ancestor.

How are organisms classified?

Organisms are classified into groups by the features they share.

What is a species?

Species are a group of organisms which can reproduce to produce fertile offspring.

List the sequence of classification

Sequence of classification: Kingdom → Phylum → Classes → Orders → Families → Genus → Species.

Funny acronym: King Philip, Come Over For Good Soup

What is the The Binomial System of Naming Species?

The Binomial System of Naming Species is an internationally agreed system in which the scientific name of an organism comprises two parts showing the genus and species.

What is meant by Genus?

A group of species that share similar features and a common ancestor. The first name in the binomial is the name of the genus that the organism belongs to.

(Example: donkeys and horses share a lot of features but they obviously different species but they belong to the same genus.)

Genus is the first part of the two part scientific name and species with similar features have the same genus

What is the importance of classification?

The classification of organisms helps show the evolutionary relationships between them.
Note - Scientists also use the DNA base sequence to help classify organisms.

What is a kingdom

Kingdom is one of the major groups into which all organisms are classified. They are also the largest group living organisms are classified into and species is the smallest one.

List the 5 Kingdoms

Animals, Plants, Fungi, Prokaryotes, Protoctists.

What are the main features of ANIMALS

Multicellular (many-celled)

It contains a nucleus but no cell walls or chloroplasts

Only feed on organic substances (substances whose molecules contain carbon ;in biology we consider organic compounds to be the ones made by living things) made by other living organisms

What are the main features of PLANTS

Consists of flowering and non-flowering plants e.g., of non-flowering plants are mosses and ferns

They can photosynthesise and they are fed by this process.

Contains nucleus and cell walls made of cellulose ( a carbohydrate that forms long fibres, and makes up the cell walls of a plant). They also often contain chloroplast.

Contains green pigment chlorophyll (absorbs energy from light and this energy is used to combine carbon dioxide with water to make glucose)

Multi-cellular (many-celled)

Plants can't move

What are the main features of FUNGUS

They have cell walls but

What are the main features of PLANTS

Consists of flowering and non-flowering plants e.g., of non-flowering plants are mosses and ferns They can photosynthesise Contains nucleus Contains chloroplast Contains green pigment chlorophyll multi-cellular cell wall made of cellulose and plants can't move