Answer:
Alkenes, A hydrocarbon with at least one carbon–carbon double bond that is unsaturated. An unsaturated hydrocarbon with at least one carbon—carbon triple bond between two carbon atoms is known as an alkyne.
Explanation:
C. Serving as a Shock absorber and cleaning agent
Answer:
Magnesium, calcium, phosphorous, sulfur these are essential nutrients for plants. These are required in trace quantity but are very important for plant life. Point A. will be correct answer.
Explanation:
As in B. starch n cellulose are composed of only carbon, oxygen and hydrogen.
As in C. These elements are not required on special occasion but are necessary throughout plant life.
As in D. C H N O is the primary component plants need but these secondary nutrients are equally necessary for growth n structure of plant.
<u><em>So answer A. Is the correct option.</em></u>
Calcium plays the most important role in structure formation of plants. Also act as messenger molecule in signaling. Deficiency of calcium caused wilting , weakened stem and ultimately death of plant.
Magnesium is the key element in chlorophyll molecule. It is necessary for chlorophyll formation.
Sulfur is another very important element in plant life, it is necessary for protein synthesis in plants.
Phosphorous plays an important role in process of cell devision , photosynthesis and respiration.
Potassium is very crucial in gaseous exchange ,it operates the opening and closing of stomata.
Answer:
Cells are sometimes referred to as "life's atoms" because there the basic units of life. All cells are surrounded by a structure called the cell membrane — which, serves as a clear boundary between the cell's internal and external environments.