<span>A hydrogen bond is the electrostatic attraction between polar molecules that occurs when ahydrogen (H) atom bound to a highly electronegative atom such as nitrogen (N), oxygen (O) or fluorine (F) experiences attraction to some other nearby highly electronegative atom.</span>
1. The correct answer is option (B) Component 3 and 4 only. The difference between the plant cell and an animal cell is the presence of the cell wall and the plastids called the chloroplasts in the plant cells. Cytoplasm is the jelly like substance present in both the plant cells and animal cells. Nucleus is the brain of the cell regulating the metabolic activities of the plant and animal cell. Cell membrane is the semi-permeable membrane covering all the cells.
2. The correct answer is option (D) Biomagnification leads to higher toxicity in tuna. Biomagnification is the accumulation of toxic substances at different tropic levels of the food chain. Fishes are a target of biomagnification due to the intake of the methyl mercury in them.
3. The correct answer is option (B) 1. Prokaryotic cells 2. Eukaryotic cells. The image 1 is a prokaryotic cell and the image 2 is a eukaryotic cell. Prokaryotes are the cells with primitive nucleus. They do not have a well-defined nucleus and the membrane bound organelles. Eukaryotes are the cells with a well-defined nucleus and all the membrane bound organelles.
I believe D would be your answer, my friend. :)
A hypothesis is a question that can be answered through an experiment. A theory is a sort of assumption that can't exactly be proved
