Chapter 8:
The Nervous System
The Nervous System
List 2 out of the 4 lobes of the brain.
•Frontal lobe
•Parietal lobe
•Temporal lobe
•Occipital lobe
Define the term sensory receptors and explain general senses vs. special senses
Sensory Receptors: Cells that respond to changes in environment and will conduct information to the brain
General Senses: touch, pressure, vibration, temperature, body and limb position, pain
Special Senses: Vision, Hearing, Equilibrium, Smell, Taste
Explain the role of hormones as chemical messengers and give an example of hormone regulation.
Chemical messengers are sent to coordinate body systems and maintain homeostasis. They specifically target cells that have specific receptors.
-Negative feedback mechanism: Increased blood level of the hormone inhibits its further release
-Positive feedback mechanism: The outcome of a process further stimulates the process (Less common than negative feedback)
List the functions of blood.
-Transportation
-Regulation
-Protection
List the functions of the cardiovascular system.
distributes blood, delivering oxygen and nutrients while removing wastes
Define and compare the CNS and PNS (include parasympathetic and sympathetic)
CNS: Central Nervous System, Consists of the brain and spinal cord, Integrates incoming information and coordinates all voluntary and involuntary nervous functions
PNS: Peripheral nervous system, Consists of ganglia and the nerves that branch from the CNS, Keeps the CNS in contact with the rest of the body
-Sympathetic nervous system: in charge during emergencies, Fight or Flight
-Parasympathetic nervous system: adjusts bodily functions during restful times, Rest and Digest
How do we perceive and maintain balance?
Vestibular Apparatus
-Semicircular canals: balance when we are moving
-Vestibule: balance when we are not moving
Explain the regulation of blood calcium by calcitonin and parathyroid hormone.
Calcitonin (CT)
-Lowers the level of calcium in the blood
-Stimulates the absorption of calcium by bone
-Inhibits the breakdown of bone
-Increases excretion of calcium in the urine
Parathyroid hormone (PTH)
-Increases levels of calcium in the blood
-Stimulates osteoclasts to break down bone, releasing calcium into the blood
List two types of anemias.
-Iron-deficiency anemia
-Hemolytic anemia: sickle-cell anemia
-Pernicious anemia
Contrast the exchange of gas in the pulmonary and systemic circuits.
-Pulmonary circuit—the right side of the heart, Contains blood low in oxygen, Transports blood to and from the lungs
-Systemic circuit—the left side of the heart, Contains blood rich in oxygen, Transports blood to and from body tissues
Describe the function of the somatic and autonomic nervous systems and the sympathetic and parasympathetic nervous systems.
Somatic nervous system: governs conscious sensations and voluntary movements
Autonomic nervous system: governs unconscious, involuntary internal activities
-Sympathetic nervous system: prepares the body for fight-or-flight
-Parasympathetic nervous system: adjusts body functions so that energy is conserved during restful times
List 1 part of the ear and its function.
Outer Ear: Functions as a receiver
-Pinna: gathers sound waves; helps determine the direction; External Auditory Canal: Leads to the eardrum;
Middle Ear: amplifier
-Malleus, incus, stapes
Inner Ear: Transmitter
-Chochela (hearing; Vestibular apparatus (body position and movement)
Compare the effects of the two pancreatic hormones, glucagon and insulin, on the regulation of glucose blood level.
•Glucagon: Increases glucose in the blood, Prompts the liver to convert glycogen to glucose and to form glucose from lactic acid and amino acids
•Insulin: Decreases glucose in the blood, Stimulates transport of glucose into muscle cells, white blood cells, and connective tissue cells, Inhibits the breakdown of glycogen to glucose, Prevents the conversion of amino acids and fatty acids to glucose
Describe the composition of blood and list the function of at least one part.
-Plasma: Medium for transporting
-Red Blood Cells: transports oxygen and carbon dioxide
-White Blood Cells: Removes waste, toxins and damaged cells and helps defend the body against disease
-Platelets: play a role in blood clotting
Describe the cardiac cycle.
1.)All chambers relax and blood passes through atria into ventricles
2.)Atria contract
3.)Ventricles contract
4.)Heart relaxes, and the cycle begins again
List two common heath problems/ injuries of the nervous system and what they do.
-Tension headaches: caused by muscle contraction in the head, face, and neck
-Migraine headaches: caused by an imbalance in the brain’s chemistry
-Stroke: interruption of blood flow by blockage
-Bell's Palsy: facial paralysis typically on one side of the face
-Spinal cord injury: loss of function below the site of injury
-Coma- trauma to the neurons, causes person to be unresponsive
Also acceptable: Transient ischemic attacks (TIAs), Hemorrhages (many types), Infections (meningitis, polio, rabies), Peripheral neuropathy
Describe the mechanism of olfactory receptors.
1.) Odors dissolve in the mucus and bind to the olfactory receptor cells, stimulating them
2.) If a threshold is reached, then the message is carried to olfactory bulbs in the brain
3.) The olfactory bulbs process the information and pass it to the limbic system and cerebral cortex
Define prostaglandins and describe their mechanism of action as compared with endocrine hormones.
-Prostaglandins have very diverse (hormone-like) effects and influence locally in places such as the reproductive system, inflammatory response, blood clotting, and body temperature
-Endocrine hormones: travel throughout the whole body
Explain how antigens determine blood type and transfusion relationships.
Antigens are proteins found on the surface of RBCs. Typically, you can only receive blood with the same antigens or your body will fight them. There are only special cases where this won't happen.
•Type A has only the A antigen
•Type B has only the B antigen
•Type AB has both A and B antigens
•Type O has neither A nor B antigens
Define blood pressure and differentiate between systolic and diastolic pressure.
Blood Pressure: The force exerted by the blood against the walls of the blood vessels.
Systolic: Highest pressure in the artery during each heartbeat, Ventricles are contracting
Diastolic: Lowest pressure in the artery during each heartbeat, Ventricles are relaxing
List 3 locations of the CNS and their functions.
-Cerebrum: The thinking, conscious part of the brain
-Corpus Callosum: Band of white matter the connects the two hemispheres
-Thalamus: Relay station for all sensory except smell, also directs moto activity, cortical arousal, and memory
-Hypothalamus: Maintains homeostasis, coordinates nervous and pituitary gland, regulates emotions
-Cerebellum: Integrates information from the motor cortex and sensory pathway, controls equilibrium and posture
-Medulla Oblongata: Reflex center to regulate involuntary functions, the pathway for sensory messages to higher brain or motor out of the brain
-Midbrain: Processes sight and sounds, reflexes
-Pons: connects spinal cord and cerebellum with cerebrum, thalamus, and hypothalamus
-Limbic System: produces emotions and memory
Also acceptable: Meninges, Cerebrospinal fluid, Grey Matter, White Matter
List three parts of the eye and their function.
1.) Sclera- Protects the eye, serves as an attachment site
2.) Cornea- Allows light to enter the eye
3.) Chorid- contains melanin which absorbs light reflected from the retina
4.) Ciliary Body- holds lens in place and changes its shape
5.) Iris- regulates pupil size
6.) Pupil- allows light to enter the eye
7.) Retina- respond to light by generating electrical signals
8.) Fovea- provides sharp vision
9.) Lens- where light enters
Relate the production of melatonin to seasonal affective disorder and name the gland that is involved.
Melatonin is inhibited by light. When it is darker for longer periods of time there is nothing inhibiting the melatonin therefore it can result in people being sleepier, grumpier, and sadder.
-Pineal Gland
Sequence the steps leading to a blood clot.
Steps that occur once a blood vessel is cut:
1.)The vessel constricts
2.)Platelets form a plug that seals the leak. Platelets cling to collagen and produce a chemical that attracts more platelets
3.)Formation of a blood clot
Describe the functions lymphatic system.
•Returns excess interstitial fluid to the bloodstream
•Transports products of fat digestion from the small intestine to the bloodstream
•Defends the body against disease-causing organisms and abnormal cells