The document provides an overview of the human body, including its structure, functions, and major systems such as the circulatory, respiratory, nervous, reproductive, skeletal, and muscular systems. It highlights key components like the cells and their functions, the digestive process, and the significance of organs, along with explanations of how these systems interact to sustain life. Additionally, it includes questions and answers related to human anatomy and physiology.

1. • 1. Introduction to Human Body
• 2. Structure and Function Of Cells
• 3. The Digestive System
• 4. The Respiratory System
• 5. The Nervous System
• 6.The Reproductive System
• 7.The Skeletal System
• 8.The Circulatory System
• 9.Muscular System

2. The Human Body is made up of a head, neck, torso, two arms and two legs. The average
Height of and adult human is about 5 to 6 feet tall.The Human body is made to stand
erect, walk on two feet, use the arms to carry and lift, and has opposable thumbs
(able to grasp).
The adult body is made up of:
100 Trillion cells
206 Bones
600 Muscles
22 Internal organs

3. There are many systems in the Human Body
Circulatory System (heart, blood, vessels)
Respiratory System (nose, trachea, lungs)
Immune System (many types of protein, cells, organs, tissues)
Skeletal System (Bones)
Excretory System (lungs, large intestine, kidneys)
Urinary System (bladder, kidneys)
Muscular System (muscles)
Endocrine System (glands)
Digestive System (mouth, esophagus, stomach, intestines)
Nervous System (brain, spinal cord, nerves)
Reproductive System (male and female reproductive organs)

4. The cell is the basic unit of structure and function in all organisms. All cells in the body
share some common structures. They are:
(1) Enclosed by a limiting boundary, a semipermeable structure called the cell membrane
(2) Have a control center the nucleus;
(3) And contain a fluid – like medium, cytoplasm, between the membrane and the nucleus.
The cytoplasm has specialized small functional units called organelles, which are
suspended in the nutrient-filled medium. Materials move across the membrane by both
passive (no energy is involved) and active (energy is expanded) processes. These are
further differentiated by what materials are moved across the membrane. Upon
disruption of the normal function of organelles, cellucal disorder results. If cells exhibit
uncontrolled cell growth and division, cancer Is a result.

5. Food provides us with fuel to live, energy to work and play, and the raw materials to build
new cells. All the different varieties of food we eat are broken down by our digestive
system and transported to every part of our body by our circulatory system.
Our Digestive system is a 9 meter long tube. The digestive process begins in the mouth,
where the teeth and tongue break up the food after it has been softened with saliva.
The food is then swallowed and travels down the esophagus to the stomach. While the
food is in the stomach, it is mixed with the mild acid which breaks the food down into a
paste similar to porridge. The food the passes, a little at a time, into the small intestine,
which is rougly 6 meters long. Here the food is broken down even further until it is
small enough to pass through the walls of the small intestine into the bloodstream. Food
that cannot be digested passes into the large intestine, where the water and minerals are
absorbed into the bloodstream. The solid waste, the feces, is then expelled from the body
through the rectum and anus.

6. The Respiratory System is the system of the body that deals with breathing. When we
breathe, the body takes in the oxygen that it needs and removes the carbon dioxide that
it doesn’t need.
First the body breathes in the air which is sucked through the nose or mouth and down
through the Trachea (windpipe). The trachea is a pipe shaped by rings cartilage. It
divides into two tubes called bronchi. These carry air into each lung. Inside the lung, the
tubes divide into smaller and smaller tubes called bronchiolies. At the end of each of
these tubes are small air balloons called alveoli. Capillaries which are small blood
vessels with thin walls, are wrapped around the alveolies. The walls are so thin and
close to each other that the air easily seeps through. In this way, oxygen seeps through
into the bloodstream, and carbon dioxide, in the bloodstream, seeps through into the
alveoli, and is then removed from the body when we breathe out. The diaphragm is the
muscle that controls the breathing process. As the diaphragm flattens, it causes the chest
to expand and air is sucked into the lungs. When the diaphragm relaxes, the chest
collapses and the air in the lungs is forced out.

7. The Human brain is a very complex, yet relatively small organ. Brain function is involved in
all of our daily activities, including breathing, planning a trip, talking, maintaining
temperature, doing homework, and walking about… The brain is also the center for
memory, emotions, intellect and behaviour. It is connected to the rest of the body through
the spinal cord and the cranial nerves.
The Nervous System is a complex network of interconnected neurons, which are information-
processing cells. There are two divisions to the nervous system (CNS) consists of the
brain and the spinal cord, and the peripheral nervous system (PNS) consists of nerves
outside the CNS. The CNS can be considered a central processing unit. Neurons carry
signals from the CNS through peripheral nerves to effectors (muscles and glands) to
carry out responses.

8. To maintain the species, humans must reproduce. In males, special cells is called a sperm
cell, whereas in females it is called an ovum. In males, the reproductive organs are the
testes, and in females they are called ovaries. The sperm cells are produced by testes
while ovaries produce eggs. The union of sperm with egg is called fertilization. The
fertilized egg, called an embryo (zygote). It grows and forms a baby inside the body of
a female.

9. The Skeleton is the name given to the collection of bones that holds the rest of our body
up. Our Skeleton is very important for us. It does three major jobs.
(1) It protects our vital organs such as the brain, the heart, and the lungs.
(2) It gives us the shape that we have. Without our skeleton, we would just be a blob of
blood and tissue on the floor.
(3) It allows us to move. Because our muscles our attached to our bones, when our
muscles move, they move the bones, and we move.
When you were born, your skeleton had around 350 bones. By the time you became an
adult, you will only have around 206 bones. This is because, as you grow, some of
the bones join together to form one bone.
Our bones don’t simply work on their own. The bones join together to form joints. The end
of each bone is covered by a tough, smooth shiny substance called cartilage. The
cartilage- coated bone- ends are kept apart by a thin film of slippery fluid that works
like oil in a car. All of this is so your bones won’t scratch and bump against each
other when you move. Our bones are held together by strong stretchy bands called
ligaments.

10. The blood is the transport system by which oxygen and nutrients reach the body’s cells, and waste
materials are carried away. The heart, a muscular organ, positioned behind the ribcage and
between the lungs, is the pump that keeps this transport system moving.
(1) Blood that is rich in oxygen appears red.
(2) Blood that is poor in oxygen appears blue.
Blood leaves the left side of the heart and travels through arteries, which gradually divide into
capillaries. In the capillaries, food and oxygen are released to the body cells, and carbon
dioxide and other waste products are returned to the bloodstream. The blood then travels in
veins back to the right side of the heart, where it is pumped directly to the lungs. In the
lungs, carbon dioxide is changed for oxygen, and this renewed blood flows back to the left
side of the heart, and the whole process begin again.

11. We depend upon on our muscles for every moment we make, for sitting or standing still.
Muscle tissue permits us to walk, run, speak and write words on a piece of paper. The
body has three types of muscles, skeletal, smooth, or cardiac, which contract or shorten to
accomplish these functions. Skeletal (voluntary) muscle is attached to bones, and extend
across the joints of the skeleton to facilitate movement of the body. Smooth (involuntary)
muscle is located in the walls of internal organs where its contraction pushes food along
the digestive tract, eliminates urine from the bladder, and is in the walls of blood vessels
to help control blood pressure. Cardiac muscle occurs only in the heart, where its
contraction pushes blood through the blood vessels of the cardiovascular system.

12. Q1 What is the name given to a blood vessel that carries blood from the heart to the body?
Ans An artery
Q2 How many bones are there in the human body?
Ans 206 bones
Q3 Which is the longest bone in the adult human body?
Ans Thigh Bone
Q4 How many muscles are there in the human body?
Ans There are 650
Q5 How many teeth in an adult human mouth?
Ans There are 32
Q6 How often do humans dream each night, on average?
Ans Apparently it’s 5 times a night!
Q7 Which helps in clotting of blood?
Ans Vitamin K
Q8 How many bones are there in an adult human being?
Ans 206
Q9 The largest part of the human brain is the
Ans Cerebrum

13. Q10 The main constituent of hemoglobin is
Ans Iron
Q11 The main function of the kidney is
Ans To remove waste product from the body
Q12 The function of hemoglobin is
Ans Prevention of Anemia
Q13 Which is the largest gland in the human body?
Ans Liver
Q14 A person which of the following blood groups is called a universal donor?
Ans O
Q15 How many bones are there in a newly born infant?
Ans 300
Q16 Which vitamins promote healthy functioning of eyes in human beings?
Ans Vitamin A
Q17 The average heartbeat per minute in a normal human is
Ans 70
Q18 Medulla oblongata is a part of human
Ans Brain
Q19 Food is normally digested in the
Ans Stomach
Q20 Rickets is a
Ans Bones