2. Mature egg cell, the largest cell in human body.
3. Spleen, the largest lymphatic organ in human body
4. The largest nerve in human body-sciatic nerve
5. The largest exocrine gland in human body-liver
6. The smallest bone in the human body-the auditory ossicle
7. The longest bone in the human body-femur
8. Gastrocnemius, the most powerful skeletal muscle in the human body.
9. The hardest substance in human body structure-enamel
10. The most advanced nerve center of human body-cerebral cortex
1 1. The thickest skin of the human body-the skin of the palms and soles of the feet.
12. Eyelid, the thinnest skin of human body
13. Hepatic portal vein, the most nutritious blood vessel in human body.
14. Renal vein, the blood vessel with the least urea in human body.
15. Pulmonary vein, the blood vessel with the highest oxygen content in human body.
16. Thyroid gland, the largest endocrine gland in human body
17. The pituitary gland, the most important endocrine organ in human body
18. The smallest blood vessel in the human body-capillary
19. The smallest lymphatic vessel in human body-lymphatic capillary.
20. The most important part of human digestive tract-small intestine.
2 1. Connective tissue is the most diverse tissue in human body.
22. Connective tissue is the most widely distributed tissue in human body.
What vitamins can the human body synthesize by itself?
Vitamins are essential trace substances for human growth and health, most of which cannot be synthesized by human body and can only be taken from food. But vitamins
Except for D.
Vitamin D is a vitamin that the human body can synthesize by itself.
My name is vitamin D, which is the only element in the vitamin family that can be synthesized by the human body. My main function in the human body is
Promote normal growth of bones and ossification of cartilage. I am also a fat-soluble vitamin, which is stored in human fat and slowly excreted.
Too much vitamin d can lead to poisoning.
There is natural vitamin D in these foods, and cod liver oil is extracted from the liver of marine fish. Plants such as fresh vegetables and yeast
Ergosterol in sex food can be converted into vitamin D2 for human use after ultraviolet irradiation.
Human body system
The human body consists of bones, muscles, tissues, organs, exercise, blood circulation, respiration, digestion, urine, reproduction, nerves and endocrine.
Unified composition, in which the nervous system coordinates the functions of the whole human body and receives external information through sensory organs.
Human tissue
The skeleton consists of about 200 bones, forming a strong and flexible skeleton. Muscle contraction ensures the joints between different bones.
Free movement: muscles attach to the bones at both ends of the joint, causing joint movement when contracting. Bones, joints and muscles form a movement system.
System.
Internal organs are mainly located in the trunk of human body. The trunk is divided into three parts from top to bottom: chest, abdominal cavity and pelvic cavity. Ribs and chest
The chest made of bones contains the heart and lungs. The diaphragm separates the abdominal cavity from the chest cavity. Most digestive organs, kidneys and spleen are located in the abdominal cavity.
Medium. There are bladder, end of digestive tract and female reproductive organs in pelvic cavity.
The brain and spinal cord constitute the central nervous system. The brain is located in the skull. The skull has a relative protective effect on the brain, while the spinal cord is hidden in the vertebrae.
In a pile of bone tubes.
The human body has multiple acupoints.
According to the theory of traditional Chinese medicine, the human body has more than 400 acupoints.
It is generally believed in martial arts that there are 365 acupoints in the human body.
What is the average blood of human body?
Scientific analysis shows that the average weight per kilogram contains 70 ml ~ 80 ml of blood (accounting for 7% ~ 8% of the weight). ...
The average human body contains about 4.7 liters of blood, including cells and liquid parts. Cells account for about 45% of human blood volume, including red blood cells and white blood cells.
Balls and platelets. All these ingredients come from stem cells made from bone marrow in the body. The liquid part accounts for 55% of the remaining blood volume and consists of plasma and solubility.
Blood protein components.
How much water should the human body supplement every day?
The average daily consumption of water by human body (through respiratory tract, urine and skin, etc.). ) is about 2500 ml, and the metabolism of substances in the body is removed.
In addition to 300 ml of oxidized raw water, at least 2200 ml should be added to the diet every day to achieve balance. To put it simply: empty before meals.
Drink water on your stomach and have soup and water for dinner.
How many muscles does the human body have?
The human body has about 639 muscles. It consists of about 6 billion muscle fibers, the longest is 60 cm, and the shortest is only1mm.
About meters. The big muscle weighs 2000 grams, and the small muscle is only a few grams. The average person's muscle accounts for 35-45% of the body weight. muscle
The total length of the inner capillary can reach 6.5438+10,000 kilometers, and it can circle the earth for two and a half times.
What are the five senses of the human body?
The so-called "five senses" refer to the five organs of the human body, such as ears, eyebrows, eyes, nose and mouth. In addition, in physiognomy, they gave
A noun is as follows:
(1) Er: It's called "Listening Officer".
(2) Eyebrow: called "longevity officer".
(3) Eye: named "Special Commissioner".
(4) Nose: It is called the "judge".
(5) Mouth: called "cashier".
The human body needs those main nutrients.
The human body needs seven kinds of nutrients, among which macronutrients include sugar, lipid, protein and water, and micronutrients.
Include vitamins, minerals and dietary fiber. Sugar substances (carbohydrates): provide energy, provide substances, and play a variety of roles.
Yes; Lipid substances: protect lubrication, provide energy and provide substances. Protein, amino acids: provide materials and play a variety of roles.
The important function of surface is to provide energy. Vitamins: Assist enzymes to play a catalytic role and participate in physiological and biochemical processes in the body. Minerals: auxiliary enzymes
Play a catalytic role, play a role in regulation, control and signal transmission. Water: the main medium of internal circulation and the key to internal balance.
Participate in some biochemical processes. Dietary fiber: change the distribution of intestinal flora, activate beneficial bacteria, improve excretion and clean intestinal tract.
What is the density of the human body?
The average density is equivalent to the density of liquid water at 4 degrees Celsius.
This is why some people can easily float on the water and look at the sky motionless!
How many cells does the human body consist of?
1. The human body consists of about 50 billion cells, and each cell center has a nucleus, and each nucleus contains 23 pairs of chromosomes respectively.
Inheriting the genetic material of parents, each chromosome contains a double helix DNA molecule, and genes with genetic factors are arranged in the DNA doublet.
On the spiral staircase.
2. Chromosome 2 1 has 225 genes, and 127 known genes have been identified, including 103 genes and 98 others.
Some genes have been identified, among which 14 gene is known to be the cause of hereditary diseases.
3. There are 23 pairs of chromosomes in each cell of human body, and there are roughly100000 genes on the chromosomes. The basic composition of these genes
The unit is DNA, and the composition and operation of genes determine our genetic characteristics such as height, fatness, susceptibility to illness or aging.
. Each gene consists of four coding sequences, named "A, G, T, C" respectively, and each coding is one.
Bases A complete set of human DNA consists of 3 billion base pairs.
Scientists tried to sequence these 3 billion base pairs correctly and clearly mark their positions on chromosomes, they said.
This is the human genome map.
4. The human genetic map contains the genetic code of about 3 billion base pairs. According to the latest map analysis, the total number of human genes is estimated.
There are about 30,000 to 40,000 orders.
5. Of the human 1 00000 genes, about100000 are functional genes that can make protein, and only 400 can be mastered by scientists.
As many as 600 kinds of growth hormone and insulin are made by specific functional genes, and there are more than 9,000 kinds to be studied.
Six. 97% of human genes are still unknown.
[1] The total number of cells that make up the human body is about 50 billion, and each cell has a DNA code of 3 billion letters. In each cell,
DNA is 6 feet long, but it is squeezed into a structure with a diameter of only 0.0004 inch.
[2] The four letters "A, G, T, C" that make up DNA carry the codes that make up all living things. These codes are grouped by three letters and matched with an amine.
Basic acid.
[3] Twenty different amino acids in human body can be arranged and combined into various protein, such as keratin in hair and blood in bones.
Red protein.
[4] It is estimated that there are about 30,000 to 40,000 human genes, about19,000 ascaris (nematodes), about 6,000 enzymes and about 4,000 mycobacterium tuberculosis.