Biology: Characteristics of Living Things - MR NIGER D

The activities which distinguish living things from non-living things are: <br> <br> <br> <br> <br> <br> <br>1. Movement: Movement is the ability of an organism to move its own body or part of its body from one place to another. Living things move in order to look for food for reproduction or run away from danger or respond to environment. <br> <br> <br> <br> <br>2. Respiration: Respiration is the exchange of gases between organisms and their environment. Living organisms take in oxygen and breathe out carbondioxide. <br> <br> <br> <br> <br> <br>3. Nutrition: Nutrition is the ability of living organisms to feed. The reason for feeding is to enable living things live and carry out life processes. Like growth, repoduction etc. <br> <br> <br> <br> <br> <br>4. Irritability: Irritability is defined as the ability of organisms to respond to stimuli. <br> <br> <br> <br> <br> <br>5. Growth: Growth is defined as an irreversible increase in size or height of organisms. <br> <br> <br> <br> <br>6. Excretion: Excretion is defined as the removal of metabolic waste products from the body. The purpose of excretion is to remove waste products of metabolism. <br> <br> <br> <br> <br> <br>7. Reproduction: Reproduction is the ability of a living organisms to give birth to youngones. The purpose of reproduction occurs in two forms. Asexual reproduction and sexual repdoduction. <br> <br> <br> <br> <br> <br>8. Death: All living organisms must die because they have definite and limited peeriod of existence.

Biology: Characteristics of Living Things - MR NIGER D

The activities which distinguish living things from non-living things are: 1. Movement: Movement is the ability of an organism...

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Level of Organisation in Organisms.

In the classification of organisms, there are developments with each group. I.e from the simple unicellular organisms to the highly developed multicelluar organisms. <br> <br> <br> <br> <br>1. The first level of Organisation is CELLULAR LEVEL - A cell is the smallest structural and functional unit of Life. In this level, a single cell may live as an individula enclosed by a cell membrane which protect the cell content. <br> <br> <br> <br> <br> <br> <br>2. A tissue is a collection of cells which have a similar structure and function. They are a group of specialised cells that stay together to perform a particular function function. Examples of tissues are hydra, muscle tissue, skeleton tissue, or bone, xylem, phloem, epidermis tissue. <br> <br> <br> <br> <br> <br>3. ORGAN Level: An organ is a group of specialised tissue that work together to perform a specific function. <br> <br> <br> <br> <br> <br> <br>4. SYSTEM level: a system is a collection of different organs that cordinate or work their activities together to perform a specific function. <br> <br> <br> <br> <br> <br> <br>5. A whole being. A collection of all the systems make up the whole being.

Level of Organisation in Organisms.

In the classification of organisms, there are developments with each group. I.e from the simple unicellular organisms to the highly develope...

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Animal Cell - Parts of Animal Cell

The man that discovered cell is Robert Hook in 1665. A cell when viewed under a light microscope comprises of the following: <br> <br> <br> <br> <br> <br>1. Cell Membrane: A thin membrane covering the cell. It is semi-permeable. It allows some substances but not other to pass in or out of the cell. <br> <br> <br> <br> <br>2. Cytoplasm: The cell without it is felly. Like transparent and consists of 90% water and some granules. Most cellular reaction take place here. <br> <br> <br> <br> <br> <br>3. Nucleus: It is a spherical body in the body which controls all the activities of the cell. It is the life of the cell and carries chromosomes which carry the genes-the hereditary material. <br> <br> <br> <br> <br> <br>4. Mitochondria: It is rod-like in shape. It is found in the cytoplasm which produce energy for the cell. It is often called the powerhouse of the cell. <br> <br> <br> <br> <br> <br> <br>5. Endoplasmic Reticulum: a system of tube and channel which connect to the nucleus and cell membranes. It transports materials between cytoplasm and cell membrane and the nucleus. <br> <br> <br> <br> <br> <br>6. Vacuole: it is an enclosure within the cytoplasm in plant cells. It is large and contain cell sap. <br> <br> <br> <br> <br> <br> <br>7 Lysosomes: it is a tiny spherical body containing digestive enzymes. They digest and destroy foreign bodies. Ribosomes - A tiny granule formed freely in the cytoplasm where they synthesize the proteins. <br> <br> <br> <br> <br> <br>8. Cell Wall: This encloses the cell membrane. It is found in a plant cell into usually made up celluslose to support the plant.

Animal Cell - Parts of Animal Cell

The man that discovered cell is Robert Hook in 1665. A cell when viewed under a light microscope comprises of the following: 1. C...

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Animal Nutrion: Types of Heterotrophic

We have already discussed the first type of heterotrophic nutrition, which is Holozoic feeding. Now we are heading to the second one. <br> <br> <br> <br> <br>2. Parasitic Feeding: A parasite is an organism that feeds on another organism called the host, while the parasite benefits, the host suffers. The association between a parasite and the host is called parasitism. Parasitism occurs in both plants and animals. In animals there are two types of parasitism: (1) Ectoparasites, (2) Endoparasites. <br> <br> <br> <br> <br> <br>Ectoparasites live on the surface body of the host eg. Lice, thick, etc. <br> <br> <br> <br> <br>Endoparasites live on the inside of the host. Eg. Tapeworm, Liverflukes etc. <br> <br> <br> <br> <br>3. Symbiotic Feeding: This is the 3rd type of heterotrophic feeding we are to discuss. It is an association in which the organisms involved are benefitting from each other. Organisms involved in symbiosis are called symbionts. Symbiosis occurs both in Plants and animals. Examples of Symbiosis in animals are cellulos digesting bacteria found in the alimentary canal of the ruminant animal. Eg. The alimentary canal accommodates the bacteria, the bacteria digests the cellulose in the diet of ruminants. <br> <br> <br> <br> <br>Other examples of symbiosis is the sea anemone and the hermit crab. <br>The cattle and the cattle egret.

Animal Nutrion: Types of Heterotrophic

We have already discussed the first type of heterotrophic nutrition, which is Holozoic feeding. Now we are heading to the second one. ...

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Modes of Nutrition - Autotrophic nutrion and Heterotrophic nutrition

There are two main forms of nutrition. <br>1. Autotrophic Nutrition. <br>2. Heterotrophic Nutrition. <br> <br> <br> <br> <br> <br> <br> Heterotrophic Nutrition: This is a form of Nutrion whereby organisms are not able to manufacture their foods themselves, hence they depend on other organisms to for their feeding. <br> <br> <br> <br> <br>Types of Heterotrophic Nutrition: <br>1. Holozoic Nutrition. This is a mode whereby organisms swallow their foods whole. Eg. Man. Holozoic Nutrition can be classified into three: <br> <br> <br> <br> <br> <br> <br>A. Carnivores: These are animals that feed on flesh alone eg. Dog, Lion etc. <br> <br> <br> <br> <br> <br>B. Herbivores: They are animals that feed on plants alone eg. Goat, cow. Etc. <br> <br> <br> <br> <br> <br>C. Omnivores: They are animals that feed on plants and flesh eg. Man, Pig.

Modes of Nutrition - Autotrophic nutrion and Heterotrophic nutrition

There are two main forms of nutrition. 1. Autotrophic Nutrition. 2. Heterotrophic Nutrition. ...

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Explanation of the Nitrogen Cycle

1. Nitrogen in the air is fixed into the soil by nitrogen-fixing bacteria and also in root of Leguminous plants (Azobacter) and Rhizobium. <br> <br> <br> <br>2. Nitrogen is absorbed by plants to form plant protein. The plant os eaten by animal. <br> <br> <br>3. During old age, plants and animals will die and decay be bacteria and fungi to form Ammonium compound in the soil. <br> <br> <br> <br>4. Ammonium compound will be acted upon by a compound called Nitrosomonas to form nitrite. <br> <br> <br> <br>5. Nitrite will be acted upon by another bacteria called Nitrobacter to form Nitrate. This nitrate is absorbed by plants, and it is in this nature that plants make use of <br> <br> <br>6. For the cycle to be completed, nitrate get back to the soil air by denitrifyng bacteria. <br> <br> <br>7 Also during Lightening, thundering and electrical discharge, atmospheric nitrogen also forms nitrate through reactor in the atmosphere.

Explanation of the Nitrogen Cycle

1. Nitrogen in the air is fixed into the soil by nitrogen-fixing bacteria and also in root of Leguminous plants (Azobacter) and Rhizobium. ...

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Enzymes: What are Enzymes?

Enzymes are organic catalysts usually proteinous in nature which speeds up chemical reaction in living cells but are not used up in the process. <br> <br> <br> <br>Characteristics of Enzymes. <br> <br> <br> <br>1. They are proteinous in nature. <br> <br>2. Enzymes have reversible reaction in substrate-Enzyme product. <br> <br>3. Enzymes are specific in their action. Each enzyme catalyses one reaction. <br> <br> <br>4. Enzymes have a specific temperature range. Above or below which they become inactive. <br> <br> <br>5. Enzymes act in very small quantity and catalyses large amount of substrate. <br> <br> <br>6. Enzymes are affected by PH - ie the acidity or alkalinity of their surrounding. They are destroyed by strong acids or alkalis.

Enzymes: What are Enzymes?

Enzymes are organic catalysts usually proteinous in nature which speeds up chemical reaction in living cells but are not used up in the proc...

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