Iron Most (two-thirds) of the iron that we have in our body is bound up in heme i.e. hemoglobin or myoglobin. Remember that hemoglobin carries oxygen in the blood and myoglobin takes oxygen from the red blood cells and carries it to tissues that need it.  Therefore, iron is very important as an oxygen carrier when in the heme form. […]
Calcium You have probably been told to drink your milk because it will build your bones. The main nutrient in milk and dairy products that is responsible for bone building is calcium. Most of the calcium (99%) in our body can be found in our bone. The other 1% is in our blood. Calcium levels […]
Electrolytes like sodium (Na+) and potassium (K+) play a key role in the transfer of nerve impulses. Nerve impulses are created by stimuli in the environment such as sight, sound, smell, taste, and touch. If the stimulus is strong enough, reaching a threshold of -55 mV, an action potential is triggered. In other words, the […]
In the last lesson I talked about the importance of maintaining body fluids, and briefly discussed the role of solutes (including electrolytes) in maintaining fluid balance. So what are electrolytes and why do we call them electrolytes anyway? Electrolytes are simply ions in solution. As you might remember, ions are charged and are therefore able […]
This week we are studying how nutrients affect fluid balance. We can’t live without fluid. The human body is about 70% water. That means every chemical reaction that takes place in our body takes place in the presence of water. Without adequate water, chemical reactions necessary for life is slowed down or stopped. The amount […]
The body has different ways in which it can regulate energy metabolism; that is, decide whether to increase energy or reduce energy production. Two main ways are highlighted in this lesson with examples, i.e., allosteric inhibition/activation, and hormones. Allosteric Inhibition and Activation Remember that allosteric regulation happens when a substance binds to a site on […]
Several minerals are involved in energy metabolism. The role of iodine, chromium, manganese and sulfur are listed below. Iodine: Use to make thyroid hormones. Thyroid hormones in turn regulates metabolism in cells. That is, they tell cells when to increase or decrease breakdown of nutrients to release energy Sulfur: A part of thiamin, biotin and […]
Protein is an important body-building raw material. The body prefers to use it for that purpose rather than to “cash it in” to make energy. It has glucose and fats to do that. However a small percentage (about 10%) is used to make energy and even more in times of starvation. So far you have […]
Body cells can suffer damage due to oxidation. This happens when atoms in the body loses an electron from its outer shell. This makes the atom highly unstable. In this unstable form (free radical), they try to regain stability by robbing an electron from nearby molecules thus causing them to become unstable. This can set […]
