How many chambers does the heart contain?
a. 3
b. 4
c. 5
d. 6

The best answer is b.  4

The human heart has  four chambers - two atria and two ventricles.

1. Right atrium -  receives oxygen-poor blood from the body and pumps it to the right ventricle.

2. Right ventricle -  pumps oxygen-poor blood to the heart.

3. Left atrium - receive oxygen - rich blood from the  lungs.

4. Left ventricle - pumps oxygen rich blood to the body.

The heart is a muscular organ. It is about the size of a closed fist. It is located in the thoracic cavity. It is protected by the rib cage and is the major organ of the circulatory system.

answer:

the water molecules are transferred from the roots to the stem or top parts of the tall tree because of important properties of water which are adhesion, cohesion and capillary action. cohesion is the property of water molecules keeps water molecules in a combined state by sharing of bonds between them at the atomic level. adhesion allows the interaction of water molecules with other substances or substrate. adhesion will cause the attachment of water molecules to the wall of the vessel (xylem) of the plant. capillary action occurs when the adhesive force to the vessel wall is stronger than the cohesive force between water molecules. capillary action mimics the transfer of water from a tube or pipe. in this way water utilizes its property to transfer water from down to top level of the plant.