D. Protein
Carbohydrates are made from three elements known as Carbon, water, and oxygen.
DNA is made up of phosphate sugar groups for the helix and nitrogenous bases for the inside.l
Lipids also are only made form carbon, water, and oxygen but in a different ratio.
Answer:
The placenta is the temporary association of fetus and maternal tissue. It is meant for nutrition and transport of different substances.
Explanation:
The placenta is a temporary association of fetal and maternal tissues. The placenta is formed from the trophoblast of the blastula. These trophoblasts form chorionic villi which later forms the placenta. The chorion and allantois also take part in the formation of the placenta. Hence, the human placenta is known as the chorioallantoic placenta. The process of formation of the placenta is known as placentation.
The placenta has several functions but the major function is to provide nutrition to the fetus. The developing fetus gets nutrition from the mother's body by the placenta. The placenta provided with blood vessels which help in the transportation of different substances. It also helps in gas exchange between the mother and baby. Thus it plays a vital role in fetal respiration. The metabolic wastes diffuse through the placenta. Placenta also stores fat, glycogen, which participates in protein metabolism.
Photosynthesis is when plants use sunlight to synthesize food from carbon dioxide. Plants are autotrophs (they make their own food) and the food they synthesize creates carbohydrates, so the correct answer is D - autotrophs produce carbohydrates.
Hope this helps.
ANSWER: A. The sun is located at the centre of the universe
They have unique no. of protons in its nucleus