Students can go through AP Inter 2nd Year Zoology Notes Lesson 3(b) Neural Control and Coordination will help students in revising the entire concepts quickly.
AP Inter 2nd Year Zoology Notes Lesson 3(b) Neural Control and Coordination
→ Nervous system and endocrine system are the two integrative systems which help in coordinating various body parts.
→ Nervous system provides an organized network of point to point connections for a quick coordination.
→ In vertebrates nervous system is divided into two parts.
- Central nervous system
- Peripheral nervous system
→ Central nervous system includes brain and spinal cord.
→ Peripheral nervous system is formed by cranial nerves and spinal nerves.
→ PNS further divided into somatic and autonomic nervous systems.
→ Brain is protected by cranium and spinal cords by vertebral column.
→ The protective membrane around the brain and spinal cord is called meninges.
→ The brain has three parts namely
- ore brain
- Mid brain
- Hind brain.
→ There are 31 pairs of spinal nerves in man., which are classified into five groups based on their location.
- Cervical – 8 pairs
- Thoracic – 12 pairs
- Lumbar – 5 pairs
- Sacral – 5 pairs
- Coccygeal – 1 pair
→ Olfactorybulb – receive impulses pertainining to smell from the olfactory epithelium.
→ Cerebrum forms the major part of brain.
→ Cerebral cortex has three functional areas.
- Sensory areas – Receive and interpret sensory impulses
- Motor areas – Control voluntary movements
- Association areas – Memory and communications.
→ Diencephalon has three parts
- Epithalamus – Non-nervous part
- Thalamus – Coordinating centre for sensory and motor signalling.
- Hypothalamus – Osmoregularity, thermoregularity, thirst, feeding etc,.
→ Midbrain consist of a pair of longitudinal bands of nervous tissue called cerebral peduncles.
→ The superior colliculi and inferior colliculi are concerned with visual and auditory functions respectively.
→ Hind brain consists of cerebellum, pons varolii and medulla oblongata.
→ cerebellum – responsible for control and coordination of locomotor movements.
→ Pons varolii – regulates the amount of air a person can take in each time.
→ Medulla includes cardiovasicular and respiratory centers, the centers for swallowing, vomiting, coughing, sneezing and hiccupping.
→ The midbrain, pons and the medulla oblongata are collectively referred to as the brain stem.
→ CSF serves as shock absorbing medium.
→ The eye is the organ of vision, located in the orbit of the skull.
→ Tears contains salts, mucus and bactericidal enzyme lysozyme.
→ Photo receptor consist of two types of photo receptor cells namely rods and cones.
→ Rods are responsible for dim light.
→ Cones are responsible for day light and colour vision.
→ Car is the site of reception of two senses namely hearing and equilibrium.