ICSE 2018: The diagram given below shows the internal structure of a spinal cord depicting a phenomenon.

ICSE 2018 

Q. The diagram given below shows the internal structure of a spinal cord depicting a phenomenon. Study the diagram and answer the questions: [5]

(i) Name the phenomenon that is depicted in the diagram. Define the phenomenon. 

(ii) Give the technical term for the point of contact between the two nerve cells. 

(iii) Name the parts numbered 1, 2 and 3. 

(iv) How does the arrangement of neurons in the spinal cord differ from that of the brain? 

(v) Mention two ways by which the spinal cord is protected in our body.

Solution:

ICSE 2018: A potted plant with variegated leaves was taken in order to prove a factor necessary for photosynthesis.

ICSE 2018

Q. A potted plant with variegated leaves was taken in order to prove a factor necessary for photosynthesis. The potted plant was kept in the dark for 24 hours and then placed in bright sunlight for a few hours. Observe the diagram and answer the questions. [5]

 

(i) What aspect of photosynthesis is being tested in the above diagram? 

(ii) Represent the process of photosynthesis in the form of a balanced equation. 

(iii)Why was the plant kept in the dark before beginning the experiment? 

(iv)What will be the result of the starch test performed on leaf ‘A’ shown in the diagram? Given an example of a plant with variegated leaves. 

(v) Draw a neat labelled diagram of a chloroplast.

Solution:

Structure of Human Sperm

In humans, there are two types of gametes been produced: in females, non-motile egg and in males, motile sperm. 

Millions of sperms race against each other to fertilize the egg. Out of millions of sperms, one sperm wins and succeeds in fertilizing the egg. When the nucleus of a human sperm fuses with egg, the process is termed as fertilization.

In this article, we will study the structure of Human Sperm in details and know about the functions each part of Human Sperm.  We will also answer interesting facts related to Human Sperm and fertilization process such as:

• What is so unique about every sperm which makes it faster than the other sperms? 
• Once a sperm fertilizes an egg, how does it prevent other sperms from entering the egg? How is polyspermy prevented?
• How is sex of a child determined?
• Is it correct to blame women for giving birth to only girl child?