Biology - Variety of living organisms

plants

animals

fungi

protoctists

Pathogen

bacteria

They are multicellular organisms

They contain chloroplasts and are able to carry out photosynthesis

they have cellulose cell walls

They store carbohydrates as starch or sucrose

Examples include flowering plants, such as cereal (e.g. maize) and a herbaceous legume (e.g. peas or beans)

They are multicellular organisms

they do not contain chloroplasts and are not able to carry out photosynthesis.

they have no cell walls

they usually have nervous coordination.

they are usually able to move from one place to another

they often store carbohydrates as glycogen

examples include mammals (e.g. humans) and insects (e.g. fly)

they have cell walls made of chitin.

They feed by extracellular secretion (i.e. out of their cells) of digestive enzymes onto food material and absroption of the organic products (this is known as saprotrophic nutrition)

some examples are single-celled (e.g. yeast)

they may store carbohydrate as glycogen

Their body is usually organised into a mycelium made from thread like structures called hyphae which contain many nuclei.

examples include Mucor, which has the typical fungal hyphal structure.

these are organisms that are not able to carry out photosynthesis.

some, like Amoeba, that live in pond water, have features like an animal cell

Chlorella, have chloroplasts and are more like plants.

These are microscopic single-celled organisms.

A pathogenic example is Plasmodium, responsible for causing malaria.

They are microscopic single-celled organisms.

They have a simple cell structure that lacks a nucleus but contains a circular chromosome of DNA.

Some bacteria can carry out photosynthesis but most feed off other living or dead organisms.

examples include Lactobacillus bulgaricus, a rod shaped bacterium used in the production of yoghurt from milk, and Pneumococcus, a spherical bacterium that acts as the pathogen causing pneumonia.

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a bacterium, virus, or other microorganism that can cause disease.

Bacteria (some are pathogenic)

Protoctists (Some are pathogenic e.g. plasmodium causes malaria)

Fungi (Some are pathogenic)

Viruses (ALL are pathogenic)

Viruses

They are small particle, smaller than bacteria; they are parasitic and can reproduce only inside living cells; they infect every type of living organism.

They have a wide variety of shapes and sizes; they have no cellular structure but have a protein coat and contain one type of nucleic acid, either DNA or RNA.

These are not living organisms.

Examples include the tobacco mosaic virus that causes discolouring of the leaves of tobacco plants by preventing the formation of chloroplasts, the influenza virus that causes 'flu' and the HIV virus that causes AIDS.