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Human Body Facts

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Human Body Facts

Human Body Facts

shape Introduction

The Human Body, composed of several different types of cells is the structure of a human being. The cells together create tissues and organ systems. The human body on the outer surface primarily consists of a head, neck, trunk (thorax & abdomen), arms, hands, legs and feet.


The main organ systems in the human body are as follows:

  1. Circulatory System – Heart, Lungs, Brain, Kidneys
  2. Respiratory System – Nose, Lungs, Pharynx, Bronchi
  3. Digestive System – Mouth, Tongue, Teeth, Pharynx, Diaphragm, Stomach, Spleen, Liver, Gallbladder, Pancreas, Small Intestine
  4. Muscular System – Skeletal Muscle, Cardiac Muscle, Smooth Muscle
  5. Nervous System – Brain, Spinal Cord, Meninges, Dura Matter
  6. Reproductive System [ Female] – Cervix, Ovary, Uterus
  7. Reproductive System [Male] – Testis, Epididymis, Gonads
  8. Skeletal System – Bones, Cartilage, Tendons, Ligaments


Human Body Facts – Some of the interesting facts about human body are as follows:

  1. The adult body is made up of: 100 trillion cells, 206 bones, 600 muscles, and 22 internal organs
  2. Every square inch of the human body has about 19 million skin cells.
  3. Every hour about 1 billion cells in the human body must be replaced.
  4. Human Brain has over 100 billion nerve cells.
  5. The adult human brain is about 2% of total body weight.
  6. The only part of the body that has no blood supply is the cornea of the eye. It receives oxygen directly from the air.
  7. The human brain has a memory capacity which is the equivalent of more than four terabytes on a hard drive.
  8. A newborn child can breathe and swallow at the same time for up to seven months.
  9. Human skull is made up of 29 different bones.
  10. The human heart pumps 182 million litres of blood during the average lifetime.


shape Human Body

Human Body Facts

Largest and strongest Bone in the body Femur (thigh bone)
Smallest Bone in the body Stapes in ear
Number of Cells in the body 75 trillion
Volume of Blood in the body 6 litres (in 70 kg body)
Number of Red Blood Cells(R.B.C.) 1. In male: 5 to 6 million/cubic mm
2. In female: 4 to 5 million/cubic mm
Life span of Red Blood Cells(R.B.C.) 100 to 120 days
Life span of White Blood Cell(W.B.C.) 3-4 days
Normal White Blood Cell(W.B.C.) count 5000-10000/cubic mm
Life span of Red Blood Cells(R.B.C.) 100 to 120 days
Life span of White Blood Cell(W.B.C.) 3-4 days
Normal White Blood Cell(W.B.C.) count 5000-10000/cubic mm
Time taken by R.B.C. to complete one cycle of circulation 20 seconds
Other name of Red Blood Cell (R.B.C.) Erythrocytes
Largest White Blood Cells Monocytes
Smallest White Blood Cells Lymphocytes
Who discovered Blood Group Karl Landsteiner
Blood Platelets count 150,000 – 400,000 platelets per micro litre
Haemoglobin (Hb) 1. In male: 14-15 gm/100 c.c. of blood
2. In female: 11-14 gm/100 c.c. of blood
Hb content in body 500-700 gm
pH of Urine 6.5-8
pH of Blood 7.36-7.41
Volume of Semen 2-5 ml/ejaculation
Normal Sperm Count 250-400 million/ejaculation
Menstrual cycle 28 days
Menopause age 45-50 years
Blood clotting time 3-5 minutes
Weight of Brain 1300-1400 gm in human adult
Normal Blood Pressure (B.P.) 120/80 mm Hg
Universal blood donor O
Universal blood recipient AB
Average body weight 70 kg
Normal body temperature 37 degree celsius
Breathing Rate at rest 12-16/minute
Number of Spinal Nerves 31 pairs
Largest Endocrine Gland Thyroid gland
Gestation period 40 weeks or 9 calendar months
Normal Heart Beat at rest 72 beats per minute
Largest Gland Liver
Largest Muscle in the body Gluteus Maximus or Buttock Muscle
Smallest Muscle in the body Stapedius
Largest Artery Aorta
Largest Vein Inferior Vena Cava
Largest and longest Nerve Sciatic Nerve
Longest Cell Neurons (nerve cells)
Minimum distance for proper vision 25 cm
Pulse rate 72 per minute
Thinnest Skin Eyelids
Weight of Heart 200-300 gm