Dear students , Over many years, there are lots of important developments in science and

2. 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.

3. Objectives • Recognize the role biology plays in current events and use the process of scientific reasoning to investigate scientific problems. • Being scientifically literate individuals in order to have ability to take part in science discussions and have ability to evaluate them • Understanding nature of science, scientific process and history of biology • Being aware of the advantages and disadvantages of modern scientific developments and applications that individuals come across 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

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

6. Who is scientist? • Scentist is a person who deals with science. A scientist must be: 1. Logical 2. Objective 3. Open mindedor not dogmatic 4. Curious and suspicious

7. 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

8. 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

9. 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.

10. 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’’.

11. 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.

12. 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:

13. 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.

15. 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.

16. 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.

17. 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.

18. 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.

19. 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

20. 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.