The bond between one carbon atom and one oxygen atom is polar but due to the fact that there is another oxygen attached to the carbon which has the same electronegativity value as the oxygen on the other side, the effect of polarity is canceled.

is non-polar because the oxygens symmetrically alligned on the opposite sides of the carbon cancel the polarity effect.
Answer:
30
Explanation:
The seed of an angiosperm is formed as a result of fertilization (fusion of sperm in pollens and the ova from ovary). According to the question, the cells of the seed which will grow into the plant contains 20 chromosomes. Seeds of angiosperms contain a tissue called ENDOSPERM that forms as a result of the unique DOUBLE FERTILIZATION in angiosperms. It occurs when one haploid sperm cell fuses with two haploid polar nuclei to form a triploid endospermic structure that serves as food for the growing embryo in the seed.
Now based on the above explanation, the diploid plant cell with 20 chromosomes will have 10 chromosomes (half as much) in its gametes as a result of meiosis. This 10 chromosomes in each gamete (sperm and ovum) fuses to form a diploid zygote with 20 chromosomes, while one haploid sperm cell (10 chromosomes) also fuses with two haploid polar nuclei (10 chromosomes each) to form a triploid endosperm with 30 chromosomes i.e. 10+10+10.
Answer:
ai) P= Red blood cell Q= Alveoli
ii)1. It gives the lungs a large surface area to volume ratio.
2. It is moist and thin.
b) P has a disc or biconcave shape which allows the O2 to bind to it with the help of a protein called haemoglobin for it to be transferred to various parts of the body.
c) Carbon monoxide will bind to the haemoglobin to form carboxyhaemoglobin causing oxygen disruption
It begins before food is eaten, the answer is C.