CH 5 questions answers
Answers
Answer:
Question 1. Who discovered cells, and how?
Answer: Robert Hooke discovered cells in 1665 while examining a thin slice of cork through a self-designed microscope. He saw that the cork resembled the structure of a honey comb consisting of many little compartments. These small boxes are called cells.
Question 2. Why the cell is called the structural and Junctional unit of life?
Answer: A cell is capable of independently carrying out all necessary activities of life. So, they are called basic or functional unit of life.
Question 1. How do substances like C02 and water move in and out of the cell? Discuss.
Answer: CO2 moves by diffusion and H2O move by osmosis through cell membrane.
Question 2. Why is the plasma membrane called a selectively permeable membrane?
Answer: It is called selectively permeable membrane because it allows the entry and exit of some substances, not all.
Question 1. Can you name the two organelles we have studied that contain their own genetic material?
Answer: The two organelles which have their own genetic material are:
1. Mitochondria 2. Plastids
Question 2. If the organisation of a cell is destroyed due to some physical or chemical influence, what will happen?
Answer: The cell will not be able to revive and lysosomes will digest it.Question 3. Why are lysosomes known as suicide hags?
Answer: When the cell gets damaged, lysosomes may burst, and the enzymes digest their own cell. Therefore lysosomes are known as suicide bags.Question 4. Where are proteins synthesised inside the cell?
Answer: The proteins are synthesised in the ribosomes that are also known as protein factories.