Chapter 1:

The five kingdoms of classification

What have you heard bout the five kingdoms of classification?

Remember: King Phillip Came Over For Great Sphagetti, for our KINGDOM - PHYLUM- CLASS - ORDER - FAMILY - GENUS - SPECIES

Lets now dive into the kingdoms of classification

the five kingdoms of classification

The features that are used to group organisms into these kingdoms are: body structure, method of getting food and method of reproduction.

Kingdom Monera

This kingdom includes the simplest and smallest living organisms. The organisms are single-celled known as bacteria

The bacteria have the following characteristics:

• They are unicellular (single celled) organisms

• The bacteria are grouped according to their shapes which can be rounded, coiled or rod-shaped.

• They have no true nucleus. Their genetic material is not enclosed by the nuclear membrane.

Useful and Harmful aspects of Monera

Some people may tend to fear bacteria, because they only imagine that bacteria cause harm. However biological studies show that bacteria can be both harmful and useful in nature.

Bacteria are harmful because:

1. They cause diseases e.g. tuberculosis and cholera in humans.

2. Action of bacteria on food makes it rot.

Bacteria are useful because:

1. They help in the process of decomposition by breaking up organic wastes.

2. They contribute to soil fertility by fixing nitrogen which is important for plant growth.

3. Some bacteria are used in treatment of sewage.

4. Some bacteria are used in industry e.g. in making of food like yoghurt.

Bacteria cause food spoilage

Bacteria used in making yoghurt

Anaerobic bacteria used in making bio-gas

Nitrogen fixing bacteria improve plant nutrition

Bacteria causes tuberculois

Bacteria on a petri dish

Kingdom Protoctista

This kingdom consists of single celled and simple multicellular organisms that possess a true nucleus unlike monera.

Examples are:

1. Amoeba: does not have a permanent shape. It moves by use of pseudopodia (pseudo- means false while podia – is to do with limb). It causes dysentery in man.

2. Paramecium: is oval shaped. It moves by use of hair-like structures called cilia. It feeds on other microorganisms e.g.

bacteria.

3. Plasmodium causes malaria in humans.

amoeba

paramecium

Kingdom Fungi

Kingdom fungi include mushrooms, yeast and moulds. Some fungi grow in wood and soil, and develop from tiny spores

Fungi have a nucleus and their cells have a cell wall made up of a substance known as chitin. They do not make their own food; instead feed on the decomposing organic matter of animals and plants.

You may already be aware that some types of fungi like mushrooms are grown and eaten while others like puff balls are poisonous. This informs you that fungi can be useful or harmful in nature.

Useful Aspects of Fungi

1. Fungi keep soil fertile by recycling organic material through decomposition.

2. Some fungi are food for humans, for example, mushrooms.

3. Manufacture of medicine, for example, antibiotic Penicillin

Yeast is a type of fungus used in baking of bread and brewing of beer in industries.

Harmful Aspects of Fungi

1. They cause diseases e.g. ringworm, candida, athletes’ foot (in animals), potato blight and leaf rust in coffee.

2. Fungi like moulds when they grow on food they cause food spoilage.

some mushrooms are edible

fungi spoil bread

bread mould

fungal disease

Activity; Sorting and identifying organisms in kingdom

monera, protoctista and fungi

What you need

1. Pictures or specimens (bracket fungus, amoeba, bacillus, spirogyra, puff ball, streptococcus, mushroom, paramecium, yeast, spirilla, euglena)

2. Group names (bacteria, fungi, protists)

3. Characteristics of different organisms (single celled, multicellular, nucleus is not surrounded by a membrane, nuclear membrane present, cell wall made up of chitin, feed on decomposing matter).

What to Do

Sort the organisms in the pictures according to their different groups using the common characteristics.

Kingdom Plantae

You have often used the word plant or plants in your conversations. Can you reflect on what organisms you have referred to as plants? You will notice that plants occur in different forms and sizes. Plants include trees, shrubs, ferns, mosses, and grasses. All plants are multi cellular. Their cells are surrounded by a cellulose cell wall and have a nucleus surrounded by a nuclear membrane. Their cells contain a green pigment known as chlorophyll that traps sunlight which the plant uses to make its own food (photosynthesis). Plants are grouped in divisions. A division is an equivalent of a phylum:

1. Non-vascular plants (Bryophytes)

2. Vascular plants (Pteridophytes and

Spermatophytes). Vascular refers to having vessels

Bryophytes

This group includes mosses, liverworts and hornworts. They are small plants that commonly inhabit shady moist places. They bear stem and leaf-like structures but no roots. They have no vascular tissue and no flowers. Bryophytes break down rocks to form soil and they prevent soil erosion. However, they weaken cement and verandas and walls if left to stay on them for long.

Pteridophytes

This group includes ferns. They grow in damp shady places. They bear stems, leaves and roots. They have vascular tissues. They do not bear flowers.

Angiosperms

Flowering plants reproduce by seeds which are formed from flowers. The seeds are enclosed in an ovary. Flowering plants are divided into two: monocotyledonous and dicotyledonous plants. Monocotyledonous plants are flowering plants which have only one cotyledon in their seeds. Most have long, narrow leaves with parallel leaf veins. Their flowers have dull coloured petals in multiples of three. Examples include grasses, maize, millet, sorghum. Dicotyledonous plants have two cotyledons in their seeds. Their leaves are usually broad and the leaf veins form a branching network. They have four or five brightly coloured petals on each flower.Examples include; beans, peas, groundnuts.

Gymnosperms

This group of plants does not bear flowers. Their seeds are not enclosed in an ovary hence these plants are sometimes referred to as “naked seed” bearing plants. They produce seeds on structures called cones. Most have needle-like leaves. Examples include pine trees, cyads and cypress.

Kingdom Animalia

We usually tend to limit the word ‘animal’ to a few particular organisms leaving out others. In this unit, you are going to learn what organisms are classified as animals. Animals are multicellular organisms. Their cells have no cell walls or chloroplasts therefore they cannot make their own food.

Most animals ingest solid food and digest it internally.

The animal kingdom can be divided into 9 main groups (Phyla); eight of these groups are animals without a backbone (Invertebrates) and the other group comprises animals that

have a backbone (Vertebrates).

Arthropods

This is the largest phylum in the animal kingdom. They live on land, in water and in air.

They have an exoskeleton that protects their bodies and prevents them from losing excessive water. Their bodies are segmented with pairs of jointed appendages (legs and antennae). The segmented body eases movement.

Arthropods consist of four classes:

• myriapods

• crustaceans

• arachnids

• insects

Myriapods

They have an elongated body with several segments.

They have one pair of antennae.

They have several legs and simple eyes.

They have one pair of legs on each body with segment.

They have a poison claw used to kill its prey.

Millipedes have two pairs of legs on each body segment. They contribute to soil fertility by barrowing in soil to aerate the soil and add humus.

examples are centipedes and millipedes

millepede

centipede

Crustaceans

They live in water or in damp places. They have two main body divisions i.e. fused head/thorax and abdomen. They have two pairs of antennae and two compound eyes. They have five pairs of jointed legs and in some species the front pair is modified into claws or pincers.

Examples

crab, crayfish and prawn

crayfish

prawn

Arachnids

They have two body parts i.e fused head/thorax and abdomen. They all have four pairs of legs. They do not have antennae or wings. They have simple eyes and breathe by book lungs. Most arachnids are predators and live on land. The tick is a parasite and transmits disease in farm animals e.g. cattle.

examples spider, tick scorpion

spider

tick

scorpion

Insects

Insects form the largest group in phylum Arthropoda. They can be found anywhere.

The insect’s body is divided into three distinct body parts, namely; head, thorax and abdomen. They have three pairs of jointed legs on the thorax. They have a pair of compound eyes except the soldier termites. Most adults have one or two pairs of wings. Some insects are harmful or useful or both harmful and useful to other organisms.

Examples include; grasshoppers, cockroaches, butterflies, houseflies etc.

grasshopper

cockroach

butterflies

housefly

Insects are the most successful living organisms contributing almost 70% of the total population of livng things on earth.

Classifying Chordates

Members of this group are also referred to as vertebrates (have a backbone). They all have an endoskeleton (inner skeleton) comprising a skull, backbone, limb bones and ribs. They have a dorsal nerve cord (spinal cord).

Most vertebrates, apart from fish, have four limbs which they use for locomotion. In birds and bats, the front limbs develop into wings for flying. A fish’s limbs are its fins, which vary in number. Snakes have no limbs.

Chordates comprise five classes:

i) Fish (Pisces) ii) Amphibians iii) Reptiles iv) Birds (aves) v) Mammals

Class Pisces (fish)

Fish live in water. Their bodies are covered with scales for protection and they have fins and tails for movement and stability in water. Fish are ectotherms. Fish use gills for gas exchange. Fish is food for many other animals. Examples include tilapia, nile perch etc

Class Amphibia (amphibians)

For the first part of the life of amphibians they live in water and use gills for gas exchange. When they become adults they develop lungs and are able to live on land and return to water to mate and lay eggs. They are also able to exchange gases through their soft moist skins. There are no scales on the skin. Amphibians are ectotherms. Examples toad, frog, salamander, newt etc

An ectotherm is an organism whose body temperature changes with the temperature of the external environment.

Class Reptilia (reptiles)

Most reptiles live on land. They have tough dry scales on their bodies which prevent loss of water and are for protection.

They use lungs for gas exchange. Like fish and amphibians, reptiles are ectotherms. Reptiles reproduce by laying eggs that have soft shells.

Common examples include tortoise, lizards, snakes, crocodile etc

QTN>why are snakes called reptiles yet they have no limbs??

Class Aves (Birds)

Birds are endothermic animals that live on land. They have feathers, beaks and scales on their legs. They reproduce by laying eggs with hard shells. Their fore limbs are modified into wings. Most birds are able to fly because of their powerful wings and light, strong bones.

An endotherm is an organism whose body temperature stays fairly the same (constant)

Class Mammalia (mammals)

Mammals are animals with hair or fur on their bodies. Like birds, mammals are endotherms. Most live on land except a few like the whale and dolphin. Mammals use lungs for gas exchange. Female mammals give birth to live young and feed the young on their own milk produced by mammary glands.

we are also mammals🤸

End of chapter Activity on Classifying chordates

What you need

Pictures of goat, rat, bat, elephant, human, whale, tortoise, python, gecko, crocodile, crested crane, crow, duck, ostrich, tilapia, shark, catfish, toad, frog, salamander

What to Do

Construct a flow chart for any six organisms in the pictures using their observable characteristics.

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