• Dear students ,• Over many years, there are lots of important developments in science and• technology. Especially, developments in biology have many impacts on every• aspect of human life. The major aim of studies in biology and technology is• to find solutions for various environmental and health problems. However,• different disadvantages can arise from these developments and studies as well.• Consequently, being a scientifically literate individual is crucial for our modern• world. We need to understand how our activities affect the environment, how• humans can take responsibility for their own health and welfare, how we• must be careful to make appropriate rules for the use of new developments• and technology. This booklet has been organised to help you find information• quickly and easily. You will learn scientific methods branches of biology,• careers in biology, famous biologist and properties of living organisms. You• will be able to engage your scientific knowledge to your daily life and gain• knowledge of terminology and concepts in order to understand our natural• world. Welcome to exciting, joyful and colourful world of biology, we wish you• a full experience of enthusiasm and curiosity.

Objectives• Recognize the role biology plays in current events and use theprocess of scientific reasoning to investigate scientific problems.• Being scientifically literate individuals in order to have ability totake part in science discussions and have ability to evaluate them• Understanding nature of science, scientific process and history ofbiology• Being aware of the advantages and disadvantages of modernscientific developments and applications that individuals comeacross in their daily life• Search for careers in biology for effective future decisions• Explain differences between living and non-living organisms• Determine the common proper ties of living organisms

What is science?

• Science is a method of obtaining knowledge about nature. The word ‘’science’’ is derived from a Latin verb meaning ‘’to know’’

Who is scientist?

• Scentist is a person who deals with science.A scientist must be:1. Logical2. Objective3. Open mindedor not dogmatic4. Curious and suspicious

Scientific method: The scientific method is a mean of gathering information and testing ideas.It is the way a scientist

• tries to find answer to his or her questions about nature. The steps involved in scientific method are simple

• and make common sense to everyone. These steps are as follows:

• 1.Definition of the problem• 2.Collecting information about the problem and forming

hypothesis• 3.Making predictions and controlled experiments• 4.Evaluating the resultsof observations and experiments.• 5.Drawing a conclusion• 6.Theory and law

1. Definition of the problem2. Collecting information about the problem and forming a hypothesis.

• Hypothesis is the possible answer to a questionabout nature ,based on observations and knowledge of the scientist.

• A good hypothesis:• a)explains all the available data• b)provides predictions to new facts.• c)must be tested by experiments

3.Forming predictions and experiments.

• After setting up a hypothesis, predictions must be made if the hypothesis works well. A good prediction shows a

• logical linkage between cause and result that are expressed by if and then.

• Observation is examining an event for a purpose .There are two types of observations:

• 1. Qualitative observations• Qualitative observation :If only the sense organs are used in the

observation ,it is called a qualitative observation.• In a qualitative observation ,the answer the questions beginning

with ‘’what’’ and ‘’how’’ are looked for. It is not• scientific.

• 2. Quantitative observations• Quantitative Observation: If measuring devices

like meter,thermometer, graduated cylinder, lever balance,

• microscope are used in an observation. It is called as quantitative observation. Quantitative observations provide

• the answer to the questions beginning with ‘’how much’’.

• The scientific testing of a hypothesis is called experimentation.

• An experiment generally includes two groups from which observations can be made. One set up is called the

• control group. The other set up is the is called the experimental group.The experimental group differs from the

• control group in only one factor or condition.

• 4.Evaluating the results of observations and experiments: If the results of an experiment do not support the

• hypothesis, it is either reversed or completely abandoned. Proposing hypothesis and testing process are repeated

• until a valid hypothesis is reached.• 5. Drawing a conclusion:

• 6.Theory and law: If the hypothesis is still found to be true after conclusions and other experiments continue to

• support it ,it is called theory.A good theory explains the facts and also predicts new facts.

• If a theory so well established by experimental evidence in many different

• situations over many years and can be disproved by no means , it becomes a scientific law.

EXAMPLE STUDY

• A.Observations• 1.Salmon are born in a shallow stream or river.• 2.Salmon travel thousands of miles to live in

the ocean.• 3.Salmon return to the very stream where

they were born to reproduce.

• HYPOTHESIS• Salmon find their home stream using their sense of smell.• EXPERIMENT• Salmon were captured and tagged as they returned to their home• stream .The fish were then transported downstream a few miles to• be released again.• The nostrils of half of the captured fish were plugged to block their• sense of smell.• The fish with the plugged nostrils are the experimental group.The• unplugged fish are the control group.

• RESULTS OF THE EXPERIMENT• Control group Experimental group• All the fish found their home stream. Half of the fish

found their home stream.• CONCLUSION• Salmon with plugged noses were not as succesful at

finding their home stream because they could not use their

• sense of smell to find their home.The hypothesis is supported.

• B.Observations• 1.A new artificial sweetener,supersweet is used

in some foods and drinks to reduce calories.• 2.Some food addivities are known to cause

cancer.• 3. Scientists from a research institution report

that another kind of artificial sweetener has been linked to bladder

• cancer in rats.

• Supersweet may cause bladder cancer.• EXPERIMENT• One hundred rats are used in a controlled experiment with

supersweet.• Fifty rats are given supersweet and fifty rats are given regular

sugar.• At the end of the experiment all the rats are autopsied for

cancer.• C o n t r o l g roup: Exactly like the experimental group except

the rats do not receive supersweet.• Experimental group: All the rats receive supersweet

• RESULT OF THE EXPERIMENT• Control group: One of the fifty rats developed bladder

cancer• Experimental group: Nine of the fifty rats developed

bladder cancer.• CONCLUSION• Supersweet appears to cause bladder cancer in rats. It

may also cause cancer in man.Further studies will need to• be conducted to determine if supersweet is an agent for

causing cancer in man.