These supplies are needed: two inflated balloons
piece of material (nylon, wool, or fur)
thread
nylon stocking
string
piece of white paper

Instructions
1. Suspend two inflated balloons by threads and tie them to a piece of string at the same point.
2. Rub each balloon with a piece of material.
A. What happens to the balloons when they are close together? What does this mean about their charge?
3. Cut two 3-by-12 inch strips of material from the nylon stocking.
4. Place both strips on a piece of white paper and rub them briskly in your hand.
5. With your fingers, lift the two pieces of nylon and hold them side by side.
B. What happens and why?
C. What electrical charge is present on the nylon strips?
6. Now bring one of the nylon strips near one of the balloons.
D. What happens? Explain what this means about the electrical charge of the nylon strip.
E. How does this investigation demonstrate the concept of ions and ionic bonding?

(You do not need to get these items yourself)

they are known to reach a speed of 21 miles per hour

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question#1

ans:

cell is the basic unit of organization of all living things. cells are often called the building block of life and it is the smallest unit of life. the study of cell is called cell biology. cell consists of cytoplasm enclosed within membrane, which contain bio-molecules such as proteins and nucleic acid.

two third of cell is water, which means that two-third of your whole body is water. the rest is the mixture of molecules, mainly proteins, lipids and carbohydrates.

question#2

ans:

organ:

an organ is a group of tissues specialized to form a functional unit. an example is the heart in animals.

organ system:

an organ system is a group of several organs whose functions are synchronized to release an effective action in a living organism. an example is digestive system.

question#3

different systems perform different function at tissue level. for example, the respiratory system facilitates breathing. in the alveoli tissue of the lungs, the exchange of oxygen and carbon dioxide molecules between the air and the bloodstream occurs by passive transport, so that oxygen is taken in and carbon dioxide and water are removed. different systems of the body carry out different functions. for example, your digestive system is responsible for taking in and processing food, while your respiratory system working with your circulatory system is responsible for taking up oxygen and getting rid of carbon dioxide.

question#4

different systems perform different function at tissue level. for example, the respiratory system facilitates breathing. in the alveoli tissue of the lungs, the exchange of oxygen and carbon dioxide molecules between the air and the bloodstream occurs by passive transport, so that oxygen is taken in and carbon dioxide and water are removed. different systems of the body carry out different functions. for example, your digestive system is responsible for taking in and processing food, while your respiratory system—working with your circulatory system is responsible for taking up oxygen and getting rid of carbon dioxide.

question#5

our body works because of the interactions that happen between organs and organ systems.  

for example:  

the heart to regulate blood flow throughout the body. the blood carries oxygen and nutrients to the cells and carries carbon dioxide and waste away from the cells. body systems work together in maintaining a constant internal environment. when this balance is disrupted, the body systems may not function properly, and human health can suffer.   you start to feel bad.

carbon atoms, hydrogen, oxygen, and nitrogen.