Science Grade 10 3rd Quarter Exam

• The nervous system is a complex network of nerve and cells that carry messages to and from the BRAIN and SPINAL CORD to the various parts of the body
• Nervous system is composed of two divisions: Central Nervous System and Peripheral Nervous System
• Central Nervous System is the processing center of the nerve network of the body
• Brain weighs about 1kg and contains billions of neurons and large number of supporting cells.
• Brain is composed of: Forebrain, Midbrain, and Hindbrain
• Cerebrum is the largest part and the center of thinking and reasoning.
• Thalamus sorts out information from the sense organs before sending them to the Cerebrum
• Pituitary gland produces hormones that regulate growth and development
• Spinal cord extends downward from the brainstem and carries messages between the brain and other parts of the body
• Hypothalamus controls hunger, thirst, sleep, and sex drive
• Midbrain relays information to the cerebrum, coordinates eye reflexes and regulates sleep
• Hindbrain is composed of Pons and Medulla Oblongata and Cerebellum
• Pons and Medulla Oblongata relay information between the brain and the spinal cord snd regulate breathing, heartbeat and digestion
• Cerebellum receives information from the sensory systems and regulates motor movements and speech
• Left brain uses logic while right brain uses feeling
• Peripheral Nervous System connects the central nervous systems to the different organs and glands of the body.
• Somatic NS is associated with voluntary control of body movement
• Under Somatic NS is sensory nerves/cranial (afferent nerves) nerves/spinal (efferent nerves)
• Autonomic NS controls involuntary actions
• Under Autonomic NS are Sympathetic NS and Parasympathetic NS
• Parasympathetic takes charge when the body is in relax mode and sympathetic takes over when the body is in alert mode
• Neuron is the basic unit of the nervous system
• Axon carry impulses away from the cell body
• Axon terminal release neurotransmitter when stimulated by an electrical signal carried by an axon
• Dendrites carry impulses toward the cell body
• Synapse is the space between two neurons
• The endocrine system contains glands that release hormones and maintains the body's balance or homeostasis
• Pancreas produces insulin and glucagon
• Hormone is a chemical messenger released into the bloodstream by one part of the body, traveling through the bloodstream to another part where it has its effect.
• Ovaries produce estrogen and progesterone
• Adrenal gland releases adrenalin, noradrenalin, and cortisol
• Thyroid gland produces thyroxin
• Testicles produce testosterone