One of the common arguments why the process of transplanting non-human organs which came from animals may be considered as an ethical act is that antigens on the surface of the non-human organs are not significantly rejected in the process. Although its research is still substantial, it is still considered as a matter of ethical issue.
Replication is performed prior to cell division
The correct answer is option (d) They allow the exchange of gases between cells in the leaf and the external environment.
Stomata are the tiny openings present in the epidermis (outer layer of cells) of the leaf. They have a pore which is guarded by the guard cells which controls the opening and closing of the stomata. Air enters and exits through the stomata.
The main funtion of stomata is to facilitate the gaseous exchange. The gas exchange that occurs when the stomata are open helps in the process of photosynthesis. During photosynthesis, carbon dioxide is taken in from the atmosphere and oxygen is released as a by-product of photosynthesis. The glucose produced is converted into the starch and stored in the leaves.
Also, water vapour diffuses through the stomata into the atmosphere by a process called the transpiration.
Thus, stomata are the structures that are mainly involved in the gaseous exchange between the cells of the leaf and the atmosphere.
Answer:
It contains all of the instructions a cell needs to sustain itself. These instructions are found within genes, which are sections of DNA made ... form that can be used by cells to produce the proteins needed to support life. ... In other cases, the RNA molecule carries messages from the DNA to other parts of the cell for processing.
Explanation:
The correct option is B. The newest crust on earth is located at the actual site of the floor spreading and as new crusts are formed they replace it. Thus, the older the crust the farther it is from the mid ocean ridge.
Sea floor spreading is a geological process in which tectonic plates splits apart from one another. It occurs at divergent plate boundaries.