My Science School

The skin is the soft outer cover/organ that forms the outer surface of the body. There are over 4 million pores in the skin. In 1 square inch of skin there lies 4 yards of nerve fibers, 1300 nerve cells, 100 sweat glands, 3 million cells, and 3 yards of blood vessels. Every square inch of the human body has an average of 32 million bacteria on it. Humans shed about 600,000 particles of skin every hour - about 1.5 pounds a year. Most dust particles in your house are made from dead skin. By 70 years of age, an average person will have lost 105 pounds of skin.

Skin shields the body against infection, dehydration, injuries, parasites, and temperature changes. It provides sensory information about the environment, manufactures vitamin D; and excretes salts and small amounts of urea. Skin provides a relatively dry and semi-impermeable barrier to fluid loss. The skin acts as a water resistant barrier so essential nutrients aren't washed out of the body.

Like a big bag of grain that takes shape on what is inside it. The largest human organ is the skin, with a surface area of about 25 square feet.

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The elbow is a complex joint formed by the articulation of three bones –the humerus, radius and ulna. The elbow joint helps in bending or straightening of the arm to 180 degrees and assists in lifting or moving objects.

The elbow can move in three ways based on slight variations in the positions of the heads of the three bones. The first is the large hinge action that is used in most movements of the arms, such as holding bags of groceries or doing bicep curls. The other movements are so small that the untrained eye rarely notices the changes in position, but they are important for motor function of the hand and wrist. Inside and outside the elbow joint, there are points where tendons attach. These tendons allow for wrist and hand movements. For example, they allow the hand to rotate.  The elbow bones are held together primarily by fibrous tissue known as ligaments. The ulnar collateral ligament, or UCL, on the inner side of the joint closest to the body is the primary stabilizer. This thick triangle-shaped band connects the head of the humerus to the heads of the ulna and radius.

The UCL can be torn or completely ruptured, which would cause severe pain on the inside of the elbow, a popping noise, swelling, and bruising. Injuries to the UCL are common among baseball pitchers, football quarterbacks, ice hockey players, and racquet sport players due to the type of motion these sports involve.

The other ligament in the elbow is the radial collateral ligament. Located on the outside of the elbow, it prevents excessive extension of the elbow.

Credit :  Healthline 

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The more times a person has been bitten by mosquitoes, the more likely it is that they’ll become desensitized over time. That means adults typically have less serious reactions to mosquito bites than children do.

Common symptoms of mosquito bites include soft bumps on the skin that may become pink, red, and itchy. In most cases, redness and puffiness appears minutes after the mosquito punctures the skin. A firm, dark red bump often appears the next day, although these symptoms may occur up to 48 hours after the initial bite. According to the American Academy of Allergy, Asthma, & Immunology (AAAAI), contact with a mosquito must be six seconds or longer to produce a reaction.

As your mosquito bite heals, the itching sensation will fade, and skin will gradually take on a less red or pink hue until it returns to its normal color. This usually takes about three to four days. Swelling will also go down after about a week.

A typical mosquito bite is less than a ½-inch across.

Credit : Healthline

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Micronutrients are one of the major groups of nutrients your body needs. They include vitamins and minerals.

Vitamins are necessary for energy production, immune function, blood clotting and other functions. Meanwhile, minerals play an important role in growth, bone health, fluid balance and several other processes.

Humans must obtain micronutrients from food since your body cannot produce vitamins and minerals — for the most part. That’s why they’re also referred to as essential nutrients.

Vitamins are organic compounds made by plants and animals which can be broken down by heat, acid or air. On the other hand, minerals are inorganic, exist in soil or water and cannot be broken down.

When you eat, you consume the vitamins that plants and animals created or the minerals they absorbed.

The micronutrient content of each food is different, so it’s best to eat a variety of foods to get enough vitamins and minerals.

Credit : Healthline

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Malnutrition refers to deficiencies or excesses in nutrient intake, imbalance of essential nutrients or impaired nutrient utilization. The double burden of malnutrition consists of both undernutrition and overweight and obesity, as well as diet-related noncommunicable diseases. Undernutrition manifests in four broad forms: wasting, stunting, underweight, and micronutrient deficiencies.

Wasting is defined as low weight-for-height. It often indicates recent and severe weight loss, although it can also persist for a long time. It usually occurs when a person has not had food of adequate quality and quantity and/or they have had frequent or prolonged illnesses. Wasting in children is associated with a higher risk of death if not treated properly. Stunting is defined as low height-for-age. It is the result of chronic or recurrent undernutrition, usually associated with poverty, poor maternal health and nutrition, frequent illness and/or inappropriate feeding and care in early life. Stunting prevents children from reaching their physical and cognitive potential. Underweight is defined as low weight-for-age. A child who is underweight may be stunted, wasted or both.

Micronutrient deficiencies are a lack of vitamins and minerals that are essential for body functions such as producing enzymes, hormones and other substances needed for growth and development.

Credit : WHO

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