< The main systems of the human body are: >
1=>Circulatory system:-
Circulates blood around the body via the heart, arteries and veins, delivering oxygen and nutrients to organs and cells and carrying their waste products away.

2=>Digestive system / Excretory system:-
Mechanical and chemical processes that provide nutrients via the mouth, esophagus, stomach and intestines.
Eliminates waste from the body.

3=>Endocrine system:-
Provides chemical communications within the body using hormones.

4=>Integumentary system/ Exocrine system:-
Skin, hair, nails, sweat and other exocrine glands.

5=>Lymphatic system / Immune system:-
The system comprising a network of lymphatic vessels that carry a clear fluid called lymph.
Defends the body against pathogenic viruses that may endanger the body .

6=>Muscular system:-
Enables the body to move using muscles.

7=>Nervous system:-
Collects and processes information from the senses via nerves and the brain and tells the muscles to contract to cause physical actions.

8=>Renal system / Urinary system:-
The system where the kidneys filter blood.

9=>Reproductive system:-
The sex organs required for the production of offspring.

10=>Respiratory system:-
The lungs and the trachea that bring air into and out of the body.

11=>Skeletal system:-
Bones supporting the body and its organs.

Here i have listed Important Questions related to Human body which we should know = Part #1 ____Click here to read next part (#2)

1.How many kidney are there in our body ?
=>2

2. What is the Length of Healthy Kidney ?
=>About 11 cm.

3. What is the width of Healthy kidney ?
=>5 to 6 cm.

4. What is the Weight of Healthy body kidney ?
=>130 to 150 gram

5. What is the Thickness of normal kidney ?
=>3 cm

6. Which kidney is Slightly lower. (Left or Right) ?
=>Right Kidney

7. How many nephrons are there in healthy kidney ?
=>About 2000000 to 2500000 (2 to 2.5 million)

8. Which part carry Urine from Kidney to Urinary bladder ?
=>Ureters

9. How many Ureters are there in our body ?
=>2 (two)

10. What is the Length of Adult body Ureters ?
=>25 to 30 cm.

12. Which part of Human body collect Urine ,and what’s the Capacity ?
=>Urinary Bladder ( Adult Urinary bladder Capacity = 350 ml to 550 ml )

13. What is Urethra ?
=>Urethra is a thin, fibromuscular tube that connects the urinary bladder to the penis. Once the bladder becomes full, urine flows through the urethra and leaves the body at the urethral meatus, which is located at tip of the penis.

14 . What is the length of Male Urethra ?
=>18 to 20 cm.

15. What is the length of Female Urethra ?
=>4 cm.

16. In which part of body the Urine is formed ?
=>Nephrons of Kidney

17. How much urine is formed by an healthy Adult in 24 hours ?
=>800 to 2000 m.l

18. What is the chemical Constituent of healthy Human Urine ?
=>95 % water ( H₂O ) , 3% Urea ( CH₄N₂O ) , 2% metabolic.

=>95 % + water and the remaining are urea 9.3 g/L, chloride 1.87 g/L, sodium 1.17 g/L, potassium 0.750 g/L, creatinine 0.670 g/L and other dissolved ions, inorganic and organic compounds.” (e.g. proteins, for example hormones, and metabolites).

=>Averages 4.8 inches (12.3 cm) and width is about 1.5 inches (4 cm).