Biology 🧬

LS : 1 - WHAT IS SCIENCE ?

Q1. What is Science ?

Ans: i) Science is the concerted human effort to understand or to understand better , the history of the natural world and how the natural world works , with observable physical evidence as the basis of understanding .

ii) It is done through observation of natural phenomena’s and through experimentation that tries to stimulate natural process under controlled conditions.

iii) Science is an organised study of knowledge which is based on experimentation .

iv) Science is a tool for searching the truths of nature. It is a way for exploring the world

v) Questioning is the primary fundamental step in scientific thinking.

vi) The word “Science” comes from the Latin word “Scientia” which means knowledge .

vii) The term science refers to the organised body of knowledge people have gained using that method.Less formally , the formally science often describes any systematic field of study or the knowledge gained from it.

Q2: What did Karl Popper and Einstein say ?

Ans: In the words of a Karl Popper “Science is a history of corrected mistakes” , and even Albert Einstein remarked of himself “ That fellow Einstein ……….. every year retracts what he wrote the year before” .

Q3: What is scientific method ?

Ans: i) A scientific method is an organised way used by scientists to prove an experiment or to answer a question or to solve a problem they have identified.

ii) They use organised ways called scientific methods which help them to plan and conduct a study.

iii) They use scientific process skills to help them to gather organise , analyse and present their information.

The steps involved in scientific method are :

i) Observe and ask questions.

ii) Form a hypothesis

iii)Plan and experiment

iv) Conduct the experiment

v) Draw conclusions and Communicate results .

Q4: What are process skills ?

Ans: i) When scientists try to find and answer to a question or do an experiment , they use thinking tool called process skills .

ii) We use many of the process skills whenever we speak , listen , read , write or think .

iii) Process skills :

Observe - use senses to learn about objects and events.

Compare - identify characteristics of things or events to find out how they are alike or different .

Classify - group or organise objects or events in categories based on specific characteristics.

iv) Process skills for interpretation:

Measure

Gather

Record

Display

Interpret

v) Process skills for prediction :

Use a model

Predict

Infer

vi) Process skills for experimentation:

Hypothesis

Plan and conduct experiment

Control variables

Q5: What are the different types of writing ?

Ans: There are four types of writing :

i) Informative writing - Describe your observation , inferences and conclusions. Tell how to do an experiment.

ii) Narrative writing - Describe something , give examples or tell a story.

iii) Expressive writing - Write letters , poems or songs.

iv) Persuasive writing - Write letters about important issues in science , writing about what we have learned in science helps others understand your thinking.

Q6: What are the different types of instruments uses by scientists?

Ans: Scientists make accurate measurements as they gather data. They use different measuring instruments such as thermometer , clocks , timers , rulers , spring balance scale and they use beakers and other containers to measure liquids.

Q7: What are the safety measures to be taken in science laboratory?

Ans: The safety measures to be taken in science laboratories are:

i) Think ahead before doing an experiment.

ii) Be aware of the work .

iii) Be careful while handling the equipment.

iv) Protect your eyes by wearing safety googles.

v) Avoid eating or drinking anything during a science activity.

vi) Protect yourself from shocks.

vii) Keep the work area clean.

Ls: 2 - CELL- THE BASIC UNIT OF LIFE

Q1:Who discovered the cell for the first time? What procedure did he follow?

Ans:i) Robert Hooke , a British scientist discovered the cell for the first time in 1665.

ii) He observed thin slices of cork (soft bark of oak tree) under a simple magnifying device which he made himself .

iii) He called these cavities as CELL.Cell is a Latin word for a little room.

Q2: Name the factors on which shape of the cell depends?

Ans: The shape of the cell depends on two factors:

i) Internal or external pressure on a cell.

ii) The functions carried out by the cell.