Answer:
The practice of growing a series of different types of crops in the same area across a sequence of growing seasons.
cells in the vegetal half of the embryo should be unpigmented those in the animal half and there should be heavily pigmented.
Explanation:
The Yolk molecules moving in the vegetal halves of the egg which is the case in most of the animals, slows down the cell division. These lesser division area or the zone demarcates the area to be vegetal pole and due to lesser cell division, it becomes unpigmented or less pigmented Based on the observation time and perspect with assuming no movement.
The pole opposite to the vegetal, is animal pole which with absence or less of yolk, gets more ability to divide and hence become more pigmented or heavily pigmented. This brings polarity to the egg and becomes telolecithal egg.
Answer: Option B.
Left atrium.
Explanation:
Pulmonary veins are veins that transmit oxygenated blood from the lungs to the heart. There are four largest pulmonary veins,two from the lungs that drain into the left atrium of the heart. The blood that is drained into the left atrium is pumped into the left ventricle through biscupid valve. The pulmonary vein function in respiration by receiving oxygenated blood in the alveoli and return it to left alveoli.