Answer:
<u>The process of photosynthesis occurs in the chloroplast</u>. Photosynthesis can be described as a process in which plants convert water and carbon dioxide into glucose and oxygen. Oxygen is the by-product of the reaction. The energy for this reaction is taken by the chloroplast by trapping light energy of the Sun.
The reaction for photosynthesis can be written as:
6CO2 + 6H2O → C6H12O6 + 6O2
<u>The process of cellular respiration takes place in the mitochondria.</u> Respiration can be described as a process in which glucose and oxygen get converted into carbon dioxide and water. Energy is released by this process which is used for many cellular activities. Hence, mitochondria is known as the powerhouse of a cell.
The reaction of cellular respiration can be summed up as:
C 6 H 12 O 6 + 6 O 2 --> 6 CO 2 + 6 H 2 O + ATP
Both, these processes provide energy for the working of cells.
Answer:
Option C. is correct.
Explanation:
According to Chargaff's rules, DNA (Deoxyribonucleic Acid) from any species of an organism should have purine and pyrimidine bases in the ratio 
This ratio is very important for solving the structure of DNA.
As per this rule, DNA is double-stranded, and covalent bonds between identical nucleotides hold the strands together.
So, Option C. is correct.
