What is meant by stimulus and reaction?
Stimulus is the change in the environment or environmental factors to to which the organism can respond or react. Theresponse shown by organisms towards or awaya stimulus is called reaction.
Differentiate between:
a. Axon and dentrite.
b. Cerebrum and cerebellum.
c. Salivary gland and thyroid gland.
d. Cranial and spinal nerve tissue.
a. Axon and dentrite.
Axon | Dentrite |
The dentrite that grows larger than others are axion. | The thread like structure that arise from the cell body of neuron is called dentrite. |
It carries impulses away from the cell body. | It carries impulses to the nerve cell. |
b. Cerebrum and cerebellum.
Cerebrum | Cerebellum |
It occupies 80% total weight of brain. | It occupies 10% total weight of brain. |
It is situated in front of mid brain and corpus callosum. | It is situated below the posterier posture of cerebrum behind the pons varilli. |
c. Salivary gland and thyroid gland.
Salivary gland | Thyroid gland |
It is exocrine gland. | It is endocrine gland. |
It has duct. | It has no duct. |
It produces enzymes. | It produces hormones. |
d. Cranial and spinal nerve tissue.
Cranial | Spinal |
They originate from brain. | They originate from spinal cord. |
Twelve pairs of cranial nerves originate from brain. | Thirty one pairs of spinal nerves originate from spinal cord. |
It communicate between brain and different parts of head. | It communicate between brain, spinal cord and different parts of body. |