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Question 15 Marks

What constitutes the central and peripheral nervous systems? How are the components of central nervous system protected? Which signals will get disrupted in case of a spinal cord injury?

Answer

Central - Brain and Spinal cord: The central nervous system consists of the brain and spinal cord. The brain is the control centerof the nervous system and is responsible for processing sensory information, initiating voluntary movements, regulatinginvoluntary functions (such as heartbeat and respiration), and higher cognitive functions (such as thinking, memory, andemotions).
Peripheral - cranial nerves and spinal nerves: The peripheral nervous system consists of all the nerves and ganglia (clusters of nerve cell bodies) outside of the brain and spinal cord. The PNS connects the central nervous system to the rest of the body,including muscles, glands, and sensory organs.
- Protection of the Components of the Central Nervous System:
- The brain is protected by the skull, a hard and bony structure that surrounds and encases the brain tissue, providing physical protection against external trauma.
- The spinal cord is surrounded by a series of protective membranes called meninges, which provide additional cushioning and support. The three layers of meninges are the dura mater (outer layer), arachnoid mater (middle layer), and pia mater (inner layer).
- Signals Disrupted in Case of Spinal Cord Injury:
- A spinal cord injury disrupts the transmission of nerve signals between the brain and the rest of the body, leading to various impairments depending on the location and severity of the injury.
- Motor signals: Damage to the spinal cord can result in paralysis or weakness of muscles below the level of injury, leadingto loss of voluntary movement and control.
- Sensory signals: Spinal cord injury can also cause loss of sensation, including touch, temperature, and proprioception (awareness of body position and movement).

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Question 25 Marks

a. List three different categories of contraception methods.
b. Why has Government of India prohibited prenatal sex determination by law? State its benefits in the long run.
c. Unsafe sexual act can lead to various infections. Name two bacterial and two viral infections caused due to unsafe sex.

Answer

a. a. Barrier method: Where physical barriers like condoms (worn over penis), diaphragm (used by females), cervical cap andcopper-T (an IUCD) are used.
b. Chemical method: Spermicidal applications by women, vaginal pills or oral contraceptive pills (OCPs) are used. OCPsare hormonal preparations which alter the hormonal level in female body. Use of OCPs is not meant for males.
c. Surgical method: Portion of vas deferens in male (vasectomy) or portion of fallopian tube in females (tubectomy) is cutor ligated. This stops release of gametes, preventing fertilisation.
b. Selective Medical Termination of Pregnancy (MTP) of female foetus using amniocentesis is the main reason behind declinefemale-male sex ratio in our country. This is because many sections of our society considered girl child as a burden. That is why Government of India prohibited prenatal sex determination by law.
Its benefits in the long run:
- Generating awareness about girls being equal helping hands in the family income.
- Banning prenatal sex determination tests.
- Banning certain ill practices in our society like dowry system.
c. Bacterial diseases transmitted through sexual contact:
(i) Gonorrhoea (ii) Syphilis
Viral diseases : (i) Warts (ii) HIV-AIDS

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