FORM ONE BIOLOGY
CHAPTER ONE: INTRODUCTION TO BIOLOGY
PART ONE: BASIC CONCEPTS AND TERMINOLOGIES OF BIOLOGY
The term ‘BIOLOGY’ is derived from the two Greek words such as “bios” which means life and “logia” which means study of.
Biology This is the branch of science which deals with the study of living and non living things. Living organisms, including their physical structure, chemical processes, molecular interactions, physiological mechanisms, development and evolution.
Biologist is a person who studies Biology.
Biology recognizes that:-
i.Cell as the basic unit of life.
ii.Genes as the basic unit of heredity.
iii.Evolution as the engine that propels the creation and extinction of species.
BRANCHES OF BIOLOGY
The following are the three main branches of Biology:-
i.Botany this is the branch of Biology which deals with the study of plants including their physiology, structure, genetics, ecology, distribution, classification, and economic importance. Botanist is a person who studies about plants ‘characteristic features.
ii.Zoology this is the branch of Biology which deals with the study of animals including their classification, physiology, development, evolution and behavior. Zoologist is a person who studies about animals’ characteristic features.
iii.Microbiology this is the branch of biology which deals with the study of microscopic organisms/microorganisms and their interactions with other living things.
The following are sub-branches of microbiology:-
i.Bacteriology is the study of bacteria.
ii.Mycology is the study of fungi.
iii.Parasitology is the study of parasites and parasitism.
iv.Virology is the study of viruses.
i.Science; this is the intellectual and practical activity which involve the systematic study of the structure and behavior of the physical and natural world through observation and experiment.
ii.Life; This is the state of being existing that distinguishes animals, plants and microorganisms from inorganic matter, such as water, rocks, stones, etc.
iii.Living things/organisms; this are individuals that display the key characteristics of life including animals, plants and microorganisms.
iv.Non-living things/non- living organisms; this are things which they can’t display the key characteristics of life including water, stones, rocks, etc.
THE CHARACTERISTICS OF LIVING THINGS
The following are the characteristics/features of living things/organisms:-
i.Growth; this is the process of increasing in physical size. For example, the upward growth of plants and animals.
ii.Nutrition/Feeding; this is the process of providing or obtaining the food necessary for health and growth.
iii.Movement; this is an act of changing physical location or position.
iv.Reproduction; this is the process by which living things produce new individuals of their own kind.
v.Excretion; this is the process of removing metabolic waste products from the body of living organisms. These metabolic wastes products include urea, ammonia, carbon dioxide, water/sweat, etc.
vi.Irritability/Sensitivity; this is the ability of an organism to respond to a stimulus/stimuli. For example, a fly landing on your skin.
vii.Respiration; this is the process in which food substances are broken down to release energy in the body of an organism.
THE IMPORTANCE OF STUDYING BIOLOGY
The following are the importance of studying biology in our everyday life situation:-
i.It helps us to understand our environment better and principles of conserving it.
ii.It helps to improve our health because in Biology there are various diseases which have been studied and the ways to avoid those diseases.
iii.It helps to avoid ourselves from magical beliefs, superstitions and other traditional taboos.
iv.It helps to know various organisms with their behaviors.
v.It helps to understand on how living organisms are classified to their different rank such as kingdom to species.
vi.It helps to overcome various obstacles caused by living organisms.
vii.It helps to understand ourselves better since we are living things.
THE RELATIONSHIP BETWEEN BIOLOGICAL SCIENCES WITH OTHER RELATED FIELDS There are various field which are related to the Biological science in various aspects, among those fields include Agriculture, Forestry, Medicine, Pharmacy, Nutrition, etc.
i.Agriculture; this is the science or practice of farming, including cultivation of the soil for the growing of crops and the rearing of animals to provide food, wool, and other products. Agriculture uses knowledge of Biology to improve plant and animal breeding. Crop, animal diseases and pests can only be overcome by applying biological knowledge.
ii.Forestry; this is the science or practice of planting, managing and caring forest resources for human benefit. Forest is a large area of land covered with trees. Use of Biological control to combat tree pests applies Biological principles and knowledge. Climate, soil and water determine the type of plants to be grown which entirely applies Biological knowledge.
iii.Medicine; this is the science or practice of diagnosis, treatment, and prevention of diseases. Biological knowledge helps to offer education to the patients on how to prevent themselves from the diseases. For example, purifying drinking water, vaccination against polio, measles and other diseases.
iv.Pharmacy; this is the profession concerned with the preparation, distribution and use of drugs. Biological knowledge helps to know the effects of drugs on living things (Pharmacology) and possible remedies/cure to be taken.
v.Nutrition; this is the process of providing or obtaining the food necessary for health and growth. Food provides substances that the body needs to build and repair its tissues and to regulate its organs and systems. Biological knowledge helps to identify the type of food required by an organism based on its quantity and quality.
PART TWO: SCIENTIFIC PROCESSES IN BIOLOGY
THE USE OF SENSE ORGANS TO MAKE CORRECT OBSERVATION
Sense organ this is an organ of the body that responds to external stimuli by conveying impulses to the sensory nervous system. There are about five sense organs such as eye, ear, skin, tongue and nose.
Each sense organ has specialized receptor cells to detect the appropriate type of physical energy or stimulation, such as follows:-
i.Eye for sight/vision.
ii.Ear for hearing/listening.
iii.Skin for touch.
iv.Tongue for taste.
v.Nose for smell.
NOTE: Students should be able to use own sense organs to make correct observations about living things on how they interact in their real life situation.
TO TAKE THE MEASUREMENTS OF MASS, LENGTH, TEMPERATURE AND PULSE RATE The scientific processes involved in the study of biology include observation, measurement and experimentation.
Observation this is the action or process of seeing something or someone carefully in order to gain information. Observation is made by using our sense organs. Through observation we can learn many scientific phenomena.
Measurement this is the assignment of a number to a characteristic of an object or event, which can be compared with other objects or events.
Measurement of mass; mass is the amount of matter in an object. Beam balance is a special instrument for measuring mass of a substance, which measured in grams (g) or kilograms (kg). Our sense organs cannot give us the true value of mass of a substance.
Picture of beam balance
Measurement of length; length is the distance from one end of something to the other end. Tape measure is one of the common instruments used for measuring length of an object. Our sense organs can just tell us which object is longer than the other, but cannot tell us to what exact length of each object is.
Picture of tape measure
Measurement of temperature; temperature is the degree or intensity of heat present in a substance or object. Thermometer is a special instrument designed for measuring the temperature of something or somebody. Our sense organs can detect the temperature of something or somebody, but cannot tell us exact temperature of an object.
Picture of thermometer
Measurement of pulse rate; pulse rate is the rate at which the heart beats, usually measured to obtain a quick evaluation of a person’s health. Stethoscope is a special instrument designed for measuring the pulse rate/heart beats of an organism. Our sense organs can measure the average pulse rate, for example, by using fingers you can count the number of heart beats per minute, but not correct way than that of stethoscope.
Picture of stethoscope
Experimentation this is the process of performing a scientific procedure, especially in a laboratory, to determine something. Experiment is a scientific procedure undertaken to a discovery, test a hypothesis, or demonstrate a known fact. The following are the seven (7) procedures/steps to be followed when conducting any scientific investigation:-
i.Identification of a problem/problem statement; problem statement provides the platform for investigating a broad range of interventions and generating options. The phenomena could be for example, “Many young people migrate from rural areas to urban despites there are a lot of economic activities in rural areas”. So what were the problems in rural areas? This is the problem to be investigated by the researcher in order to come up with the answers.
ii.Hypothesis formulation; hypothesis is a tentative or suggested answer, an assumption or a proposed solution to the problems under investigation. It can be stated as either negative or positive. For example, by using the problem statement above you can suggest that “Many young people migrate from rural areas to urban due to an outbreak of communicable diseases such as cholera”. This hypothesis must therefore be tested by experiment.
iii.Experimentation; so after making the hypothesis, Researcher must performing a scientific procedures so as to know the reality of the hypothesis which has been formed. For example, due to the problem above, a Researcher must go to the rural areas and conducting the experiment in relation to the problem.
iv.Observation; these done by using sense organs such as eyes, ears, etc. so as to determine the reality of the problem.
v.Data recording; the Researcher must record the data whatever she/he observes in His/hers experiment so as to determine the reality of the problem.
vi.Data interpretation; once a Researcher has collected data in the field, she/he should try to explain the meaning of data in relation to the purpose of the experiment. In this step, a Researcher can find whether the hypothesis is correct or not correct.
Conclusion; the conclusion is based on the collected data. The conclusion is either confirmation or rejection of the hypothesis under investigation.
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