BIOLOGY SS 1- FIRST TERM Organization of Life 1. Recognizing living things 2. Classification of Living Things – Kingdoms: Monere, Protista and Fungi, Plantae and Animalia 3. The cell 4. The Cell and its Environment 5. Some Properties and ‘Functions of the Cell 6. Tissues and Supporting Systems 7. Nutrition in Animals BIOLOGY SS […]
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These are organic compounds that are essential for proper growth, development and functioning of the body. Vitamins are required in very small quantities They are not stored and must be included in the diet Vitamins Band C are soluble in water, the rest are soluble in fat Various vitamins are used in different ways
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COMMON DENTAL DISEASES – Carries, Causes, Treatment & Periodontal Diseases Dental Carries Dental carries are the holes or cavities that are formed as acid corrodes enamel and eventually the dentine Causes This is caused by bacteria acting on the food left between teeth and on the cusp Acids are formed that eventually corrode the enamel
TYPES OF MAMMALIAN TEETH Mammals have four kinds of teeth The incisors are found at the front of the jaw They are sharp-edged and are used for biting The canines are located at the sides of the jaw They are pointed and are used for tearing and piercing The premolars are next to the canines
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ENZYMES – FULL EXPLANATION Enzymes are biological catalysts that increase the rate of chemical reaction in the body. They are all produced inside cells. Some are intracellular and they catalyse reactions within the cells. Others are extracellular and are secreted out of the cells where they work e.g. digestive enzymes Properties of Enzymes Enzymes
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NUTRITION IN ANIMALS – HETEROTROPHISM Meaning and Types of Heterotrophism This is a mode of nutrition whereby organisms feed on complex organic matter from other plants or animals All animals are heterotrophs Their mode of feeding is also said to be holozoic to distinguish it from other special types of heterotrophic nutrition namely: Saprophytism Parasitism
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Proteins are the most abundant organic compounds in cells and constitute 50% of total dry weight Proteins are compounds which are made up of carbon, hydrogen, nitrogen, oxygen and sometimes sulphur and phosphorus. The structural units of proteins are amino acids The nature of a protein is determined by the types of amino acids it
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POLYSACCHARIDES If many monosaccharides are joined together through condensation, a polysaccharide is formed Polysaccharides may consist of hundreds or even thousands of monosaccharide units Examples of polysaccharides: Starch – storage material in plants Glycogen is a storage carbohydrate in animals like starch, but has longer chains Isulin – a storage carbohydrate in some plants e.g.
DISACCHARIDES – WELL EXPLAINED These contain two monosaccharide units. The chemical process through which a large molecule (e.g a disaccharide) is formed from smaller molecules is called condensation and it involves loss of water Common examples of disaccharides include sucrose, maltose and lactose Disaccharides are broken into their monosaccharide units by heating with dilute
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MONOSACCHARIDES These are simple sugars The carbon atoms in these sugars form a chain to which hydrogen and oxygen atoms are attached Monosaccharides are classified according to the number of carbon atoms they possess The most common monosaccharides are: Glucose – found free in fruits and vegetables Fructose – found free in fruits and in
PROCESS OF PHOTOSYNTHESIS What is photosynthesis? Photosynthesis is the process by which green plants and certain other organisms transform light energy into chemical energy. During photosynthesis in green plants, light energy is captured and used to convert water, carbon dioxide, and minerals into oxygen and energy-rich organic compounds. A general equation for photosynthesis is: Carbon (IV)Oxide+Water light energy—Glucose+Oxygen chlorophyll 6CO2+6H2O light C6H12O+6O2 chlorophyll The reaction occurs in two main
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Active transport is the movement of solutes such as glucose, amino acids and mineral ions; From an area of their low concentration to an area of high concentration. It is movement against a concentration gradient and therefore energy is required. As such it only takes place in living organisms The energy needed comes from respiration.
CHEMICAL COMPOUNDS WHICH CONSTITUTE LIVING ORGANISMS All matter is made up of chemical elements, each of which exists in the form of smaller units called atoms Some of the elements occur in large amounts in living things These include carbon, oxygen, hydrogen, nitrogen, sulphur and phosphorus Elements combine together to form compounds Some of these
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COMPARISON BETWEEN ANIMAL CELL AND PLANT CELL Plant Cell & Animal Cell Cell Specialisation Cells are specialised to perform different functions in both plants and animals Example; Palisade cells have many chloroplasts for photosynthesis Root hair cells are long and thin to absorb water from the soil Red blood cells have hemoglobin which transports oxygen
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WATER RELATIONS IN PLANT AND ANIMAL CELLS The medium (solution) surrounding cells or organisms is described by the terms hypotonic, hypertonic and isotonic. A solution whose solute concentration is more than that of the cell sap is said to be hypertonic A cell placed in such a solution loses water to the surroundings by osmosis
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THE CELL – Cell membrane, Cell wall, Plasma Membrane, Endoplasmic Reticulum & Ribosomes, Goigi Bodies, Mitochondria Introduction What is a cell? The cell is the basic unit of an organism. All living organisms are made up of cells. Some organisms are made up of one cell and others are said to be multicellular. Other organisms
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MATERIALS NEEDED FOR COLLECTION OF ORGANISMS Knives to cut portions of plant stem/root or uproot Polythene bags to put the collected plant or specimens Insect collecting jars Insect killing jars Hand gloves Sweep nets Pooters Traps Observation of Organisms Observe the plant/animal in its natural habitat before collecting Identify the exact place -on surface,
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INTRODUCTION TO BIOLOGY What is Biology? Biology derived from Greek words – BIOS meaning LIFE and LOGY meaning STUDY or KNOWLEDGE. Biology means “life knowledge”. It is the study of living things/organisms BRANCHES OF BIOLOGY Botany – study of plants Zoology – study of animals Microbiology – study’ of microscopic organisms Morphology – study
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CHARACTERISTICS OF LIVING THINGS Life defined through observations of activities carried out by living things; Nutrition Nutrition is the processes by which food/nutrients are acquired/made and utilized by living organisms. Green plants and certain bacteria make their own food. All other organisms feed on complex organic materials. Respiration This is the breakdown of
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The Meaning of HIV/AIDS The Human Immunodeficiency Virus (HIV) or Acquired Immune Deficiency Syndrome (AIDS) was first reported in the Los Angeles city of California in 1980. It was first diagnosed in a gay man (homosexual). AIDS is the most severe form of HIV infections. The virus only lives in human and not in animals,
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