The nervous system comprises the central nervous system (the brain and the spinal cord) and the peripheral nervous system, the nerves running to and from the brain (cranial nerves) and spinal cord (spinal nerves). A chain of ganglia runs close to the spinal cord and is associated with the autonomic nervous system, which controls internal organs. Autonomic nerve fibres are also contained within the peripheral nerves.
The endocrine system is a collection of ductless glands scattered throughout the body. Endocrine glands pass their secretions (known as hormones) directly into the bloodstream so they are always adjacent to blood vessels.
The Nervous System senses and controls every part of the body through its many nerves.
Sensory Receptors which are located throughout the body constantly send through the nerves to the Brain. The Brain the digests this information, and then will decide on the appropriate action to be taken. It executes this by sending additional information out to the target cells through the other nerves.
An example of this could be if you touched a hot sauce pan, the Sensory Receptors would register the pain almost instantaneously. This information will travel through the nerves to reach the Brain. The Brain understands that your hand is in danger of being hurt or injured in the current position that it is in and then the Brain sends more information down to the other nerves which in turn will tell the muscle in the body to jerk or pull the hand away from the hot pan.
D2 – Evaluate the importance of homeostasis in maintaining the healthy functioning of the body.
i) Evaluate the importance of homeostasis in maintaining the healthy functioning of the body.
Homeostasis is essential for the body to function correctly. We have looked at how the heart rate, breathing rate, temperature and blood glucose levels are controlled. It is essential to control sodium levels within the body.
1) What is sodium used for in the body?
Sodium is an electrolyte and used in balancing water in the body, in generating electrical messages necessary for muscle contraction and nerve transmission, and to control heart rhythms. Sodium is needed for muscle contractions, nerve transmissions, maintaining pH balance, and hydration. Sodium regulates the fluid outside of the cells and is needed to pump fluid into the cells as potassium carries by-products out.
2) Where do we obtain sodium from?
Sodium occurs naturally in eggs, meat, vegetables and milk. It is added to many processed foods. Sodium is a part of everyone’s daily diet
Sodium is one factor in the development of high blood pressure. It is a component of salt. E.g. Table Salt is 40% Sodium and 60% Chloride. Sodium is naturally present in most food. It is the Sodium portion of Salt that is important to people who are concerned about High Blood Pressure. Most of the Sodium in processed foods is added to preserve or flavour them. Salt is the major source of this Sodium. Salt is added to most canned and some frozen vegetables, smoked and cured meats, pickles and sauerkraut (Sour Cabbage).It is used in most cheeses, sauces, soups, salad dressings and many breakfast cereals.
Sodium is also found in many other ingredients used in food processing.
3) How does the body control sodium levels?
Sodium helps to maintain fluid balance; regulates your blood pressure; aids muscle contractions and also nerve transmissions. The body continually regulates its handling of Sodium. When a person eats too much or too little sodium, the intestines and kidneys respond to adjust concentrations to normal. During the course of a day, the intestines absorb dietary sodium while the kidneys excrete a nearly equal amount of Sodium into the Urine.
The concentration of Sodium in the blood depends on the total amount of Sodium and water in The Circulatory System - Arteries, Veins and Capillaries. The body regulates Sodium and water in different ways, but uses both to help correct Blood Pressure when it is too high or too low.
4) What are the symptoms of too much or too little sodium in the body?
If the body has too little Sodium (Hyponatremia), the body can either increase Sodium levels or decrease water in the body. Too high a concentration of Sodium (Hypermatremia), can be corrected either by decreasing Sodium levels or by increasing body water.
If you don’t have enough Sodium in the body you may begin to feel some different effects. For example: dizziness, confusion, tiredness and also muscle cramps.
by
jesshc (student)
