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The surface area of cerebrum is increased by gyri, sulci

(C) Cerebrum

(D) Cerebrum

A) Nervous system

1. Blinking: Involuntary action or reflex action. 

2. Cleaning the table: Voluntary action. 

3. Playing on the keyboard: Conditioned reflex. 

4. Salivating when food is put in the mouth: Involuntary or Reflex action. 

5. We close our ears when we hear unbearable sound: Involuntary or reflex action.

(d) +1 and +1 respectively

(a) Both A and R are correct and R is the correct explanation of A.

i) Human nervous system

ii)

A. Cerebellum 

B. Medulla oblonga

iii) Pituitary gland

iv) Cerebrum

(B) Abscisic acid

(C) Adrenalin

B) stimulate positive phototropism

The examples for endocrine glands are pituitary gland, thyroid gland, parathyroid, adrenal, hypothalamus, pancreas, thymus, testes and ovaries.

Involuntary actIon: It occurs because of choice. It may or may not occur with the awareness of the organism performing it.

The movements which are not under the control of the conscious mind are called involuntary The movements which are not under the control of the conscious mind are called involuntary actions. 

Example : Respiration, circulation, digestion.

1. The information acquired at the dendritic tip of a nerve cell sets off a chemical reaction that creates an electrical impulse. 

2. This impulse travels from the dendrite to the cell body and then along the axon to its end. 

3. At the end of the axon the electrical impulse sets off the release of some chemicals. 

4. These chemicals cross the gap or synapse and start a similar electrical impulse in a dendrite of the next neuron. 

5. A similar synapse finally allows the delivery of such impulse from neurons to other cells such as muscles or glands.

1. Each nerve cell consists of a cell body, dendrites, and axon. 
2. Synapse is the functional region of contact between two neurons.
3. Basing on the pathways followed nerves are classified mainly into three different types.
4.  Afferent or sensory nerves carry information from the sense organs to the central nervous system.
5. Efferent or motor nerves carry messages from the central nervous system to parts that or the effector organs.

Nerve transmission from stimulus to a response can occur at a maximum speed of about 100 meters per second.

The part of the brain that maintains the equilibrium is cerebellum.

1. The structural and functional unit that carries out reflex action is called a reflex arc. 

2. It consists of five components. 

3. They are receptor, a sensory nerve, a association neuron, a motor nerve and an effector organ.

Reflex arc: The path followed by a nerve impulse starting from the receptor and finally reaching the effector is called reflex arc; a Structural and functional unit that carries reflex action.

The structural and functional unit that carries reflex action is called reflex arc.

The given diagram is the sensory Neuron. They are also called Afferent nerves. 

Function: They carry messages towards central nervous system (Brain or spinal cord) from nerve endings on the muscles of different sense organs, that sense the change in surroundings.

1. Gibberellins has a significant effect on stem elongation. 

2. It also increases the leaf lamina area. This is due to stimulation of cell division and cell elongation to both leaves and stem. 

3. It leads to the formation of seedless fruits.

4. Gibberellins along with auxins promote cell elongation and leaf expansion. 

5. Parthenocarpy is induced in fruits like apple and pear with spray of Gibberellins. 

6. These substances are also known to induce enzymes like amylase, protease, lipase, etc. at the on set of seed germination and break the seed dormancy. 

7. These substances are used for fruit setting and also for growing seed less fruits. 

8. In beverages industry gibberellin is used to stimulate amylase activity in barley seeds. This is known to enhance the malting of barley grains.

C) Short plants to long plants

1. The plant responding to stimulus is mimosa pudica is the example.

2. Mimosa pudica leaves have pad like sweelings at the base are called PULVINI. 

3. Here cells contain water and large intercellular spaces. Due to water pressure pulvini hold the leaf errect. 

4. When we touch the leaves, an electrical impulse is generated due to plant hormone. 

5. Because of this hormone water in the pulvini cells which are closer to the leaf vein migrate to other side’of the cells. 

6. Then pulvini loss its fitness hence leaves become fold. After 20 to 30 minutes water comes back leaves become errect.

1. Phototropism: Response of plant to light cite example is called phototropism. 

Ex: sunflower 

2. Geotropism: Response of a plant to gravitational force 

Ex: root growth of plant 

3. Hydrotropism: Response of root to water availability in the soil. 

Ex : Plants which are growing very close to rocks and walls.

4. Thigmotropism: Response to make contact or touch is called Thigmotropism. 

5. Chemotropism: Response to chemical is called chemotropism (Stigma secretes sugary substances)

1. Cytokinins are capable of stimulating cell division along with auxins. 

2. They promote cell elongation. 

3. They have ability to delay the pocess of ageing in leaves. 

4. Cytokinins can prolong the life of fresh leaf crops like cabbage, spinach. 

5. They are also used for keeping the flowers fresh. 

6. Cytokinins are most effective in breaking dormancy of buds and seeds. 

7. The levels of cytokinins decrease in senescing leaves.

i) Synapse. 

ii) It is a functional region of contact between two neurons where infromation from one neuron is transmitted to another neuron.

Aelius Galenus (Galen) – AD. 129-200:

• Galen was a prominent Greek-speaking Roman physician, surgeon end philosopher.
• Galen was the originator of the experimental method in medical investigation.
• He proved that urine was formed in the kidney.
• His most important discovery was that arteries carry blood. He explained the differences between venous and arterial blood.
• Galen explained the difference between motor and sensory nerves.

Gibberellins help in the germination of seeds and sprouting of buds; elongation of stems and breaking the dormancy in seeds and buds.

Gibberellins help in the germination of seeds and sprouting of buds; elongation of stems and breaking the dormancy in seeds and buds.

Directional movements in plants in response to specific stimuli like light, chemicals, etc., are called tropic movements.

Cytokinins promote cell division; the promotion of sprouting of lateral buds, delay the aging in leaves, the opening of stomata.

Ethylene is useful in ripening fruit.

The bending of plants towards light is phototropism.

The downward movement of a plant in response to gravitational force is called geotropism.

Closing of stomata and seed dormancy are caused by the phytohormone Abscisicacid.

Auxins were discovered by Went

Auxins are responsible for cell elongation and differentiation of shoots and roots.

Major plant hormones and their action:

31 pairs of spinal nerves are present.

Answer is (B) 31

(D) Grey matter

These can be divided into voluntary actions, involuntary actions and reflex actions. Voluntary actions: Walking, laughing, reading Involuntary actions: Digestion of food, heart beat Reflex actions: Blinking of eye lids

Answer is C) A or B

The major parts of neuron are cell body or cyton, dendrites and axon.