The eyes close just before a sneeze due to a reflex action as the eyes and the nose are connected by cranial nerves. The sneeze sends a stimulation that travels to a nerve in the brain and a nerve in the eyelids triggering the eyes to close.
A:According to the National Center for Biotechnology Information (NCBI), the human stomach is an elastic organ that can expand to hold from 0.25 to 1.7 L of contents without causing any discomfort. The average human stomach has a capacity of roughly 1 L, or a little more than a quart.
A:The blood transports oxygen, carbon dioxide, nutrients, water, hormones, waste substances and heat. The waste substances are moved to the liver and kidneys, which remove toxins from the blood. Urea is moved from the liver to the kidneys.
A:When the body produces too much adrenaline, a person likely has phaeochromocytoma, a rare tumor of the adrenal medulla, according to the Society for Endocrinology. Symptoms of this condition include high blood pressure, fast heartbeat, palpitations, excessive sweating, weight loss and anxiety.
A:When the body becomes dehydrated, a variety of symptoms can occur, including weakness, dizziness, decreased urination and heart palpitations, according to WebMD. Dehydration occurs when the body loses more fluids than it takes in. Additional signs of dehydration include increased thirst, swollen tongue and an inability to sweat.
A:According to HowStuffWorks, the famous myth that the tongue is the strongest muscle in the body is not true. The tongue is made up of skeletal muscle fibers, allowing its owner to control it voluntarily. It is an essential part of the digestive system in keeping food between the teeth for chewing, the first part of the digestive process. Several other muscles have strength in different capacities that outweigh the strength of tongue.
A:According to The Franklin Institute, there are three types of blood vessels, each with its own function. Veins carry blood back to the heart, arteries carry blood away from the heart and capillaries connect arteries to veins.
A:According to the Western Journal of Medicine, the knee is stabilized by the shape of the joint and the ligaments accompanying it. The joint is shaped by the local bone protuberances and the surrounding cartilage. The many ligaments that support the knee joint include the cruciate (cross-shaped) and collateral ligaments.
A:Duke Magazine reports that the bones in the head continue to grow throughout a person's lifetime. The cheekbones move backward and the forehead moves forward as a person ages. The facial bones also seem to tilt forward as a person gets older.
A:Most males have reached their full height by age 16, but their muscles still grow. Much of the height increase comes from a growth spurt between ages 12 and 16. During this period, boys often add as many as 12 inches. They also put on weight, and this gain typically ranges from 15 to 65 pounds.
A:On average, it takes the human body approximately two to three hours to excrete a liter of water through the bladder. This is dependent on several factors, including the absorption of water, the components in the water, if dehydration is present, the time of day and the general health of the person.
A:Better Medicine states that hunger is the result of a complicated group of interactions controlled by the body's endocrine, digestive and neurological systems. These systems send chemicals to the brain to indicate both hunger and fullness. When a person consistently experiences excessive hunger, it can be a sign of illness.
A:The hammer in the ear, also called the malleus, transmits sound vibration to the anvil from the eardrum. The hammer and the anvil, also called the incus, are two of three very small, linked and movable bones in the ear. The other is the stirrup or stapes. Together, these three bones transmit sounds through the inner ear. InnerBody states that "the small bones create fluid membrane waves by converting compression sound waves from the eardrum."
A:Fat supplies calories, provides essential fatty acids and serves as the storage substance for the excess calories of the body, according to the health guide of The New York Times. It helps move certain vitamins through the bloodstream, and it maintains healthy hair and skin.
A:There are significant differences between the human brain and the brains of sheep; for instance, the human brain is larger in size and heavier when compared to a sheep’s brain. An adult human brain weighs 1,300 to 1,400 grams, while the brain of a sheep weighs in at around 140 grams. Sheep brains have less ridges and contours in comparison to human brains.
A:Meissner's corpuscles, also known as tactile corpuscles, are nerve endings that are responsible for detecting a light touch to the skin. The are considered a type of mechanoreceptor since they are responsive to physical pressure. Meissner's corpuscles have the lowest sensitivity threshold of any type of mechanoreceptor; they can sense vibrations with frequencies as low as 10 Hertz.
A:An acupressure practitioner can send someone to sleep quickly by applying pressure on one or several of his pressure points. For example, applying pressure on the middle of the inner side of the wrist, between the eyebrows or on the center of the breastbone can help induce quick sleep.
A:A high instep is a type of foot structure in which the arch of the foot does not fall flat when bearing weight. This condition, also known as a supinated foot and Pes Cavus, occurs in about 8 to 15 per cent of the population, according to MedicMD.