Compared to arteries, valves have no pulse, have thin walls and have valves that prevent backflow of the blood. The pressure in the veins is less than that of the arteries, hence, there is no pulse. They are nearer to the surface of the skin. It also connects arteries and capillaries which transport blood all throughout the circulatory system.
Answer:Almost 2/3 of our body store of iron is found in the hemoglobin in our blood
Explanation:
Air pollution has become an extremely serious problem. Air pollutants affect both plants and animals. Under polluted conditions, plants develop different physiological, morphological and anatomical changes. Pollutants cause damage to cuticular waxes by which then they enter the leaves through stomata. This further leads to injury to plants which can be either acute or chronic. Changes in stomata due to air pollutants which seem to be small can be of great consequence with respect to survival of the plant during stress. These effects can further lead to disturbing the water balance of leaf or whole plant. Respiration also gets affected because of the exposure of plants to air pollutants. The present paper deals with the effect of air pollutants on stomata as well as on respiration leading to affect gaseous exchange.
Answer:
Upon nutrient limitation, budding yeast will produce daughter cells less than 20% of the mother cell size. This asymmetric division may select for growth functions that are efficient over a larger range in cell sizes, such as exponential growth. In turn, efficient growth over a large size range lessens the pressure to have precise size control.
Explanation:
In wild-type cells growing in nitrogen-rich medium, the size threshold to enter mitosis is high, and the G1/S size control is cryptic because cell division produces daughter cells with a size greater than the minimum required to initiate S phase. In these conditions, G2 is long and G1 is short. However, the cell size threshold to enter mitosis is greatly reduced when wild-type cells are shifted to medium with a poor nitrogen source, such as minimal medium with proline, isoleucine, or phenylalanine. In these conditions, wild-type cells initiate mitosis at a reduced cell size, generating two daughter cells that are smaller than the critical size threshold required to progress through G1/S
