Answer:
La energía del organismo vivo no se puede perder ni ganar del entorno externo.
Explanation:
D. friction pulls the skates wheels westward
Answer: D - Lipids
Lipids provide a long term energy storage because they contain longer C-H bonds compared to the other organic molecules, making it easier for them to store larger amount of energy. Moreover, upon burning they produce twice the amount of calories compared to that of the carbohydrates.
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.
