Answer:
The correct answer will be option-E
Explanation:
The structure of DNA revealed by Watson and Crick showed that Two strands of DNA are present in the intertwined state forming helix representing DNA as a double helix.
Each strand of DNA is made up of the monomer unit of DNA called nucleotide where each nucleotide binds to another nucleotide through weak covalent bond called phosphodiester bond.
The phosphodiester bond is formed between the 3’-OH group of one nucleotide to 5’ phosphate group of another nucleotide. In this way, the phosphate-sugar molecule forms the backbone of the DNA molecule.
Thus, option-E is the correct answer
Answer:
stop sending signals to the brain
Explanation:
Answer: To allow efficient distribution of materials within the body
Explanation:
Circulatory system in mammals especially human provides an efficient way of distribution of materials within the body.
This is made possible by blood and lymph which represent the media for circulation in humans
The correct answer is fire extinguisher.
Before someone starts to fuel a boat there should be fire extinguisher.
When a person is fueling the fuel might overfill and spill the fuel into engine or to passenger compartment and this can increase the risk of fire explosion and if spilling fuel to the water will harm the marine environment that is why a person should have fire extinguisher when fueling.
Some precautions which are taken when refueling are,
1. Refueling should be done on daylight when artificial light is not needed.
2. When refueling a person should not smoke.
3. Portable tank should be refueled in the tank and not in the boat.