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:
they carry out experiments to understand it
Explanation:
Scientists raise hypotheses which are tested by experiments made under controlled conditions in order to explain a particular topic. When a hypothesis is confirmed by the experimental data, the evidence obtained from this experiment provides the basis to increase the scientific knowledge about a particular issue. In consequence, experimentation can be considered as a critical step in the scientific method and research aims to advance knowledge of a particular phenomenon by confirming a hypothesis, which must be testable (i.e. verifiable as a result of further experimentations).
As any other ancient civilization, the Sumerians were traders as well. And they had a few good reasons to do this.
Because they traded, their trading partners were less likely to attack them, because it would hurt their economy as well. Furthermore, they didn't produce everything they needed and traded those goods with goods which they produced too much of.
And lastly, through trade they could also get exotic goods which they would have never gotten otherwise.
Answer:
you would use your muscles from your legs and your body to get up from your bed and go to your fridge, your muscular system helps you up by being a structure for the muscles to apply force, you will use arm muscles for getting out cookies and milk. Then you will drink and eat your cookies and milk with your jaw muscle and send it down your esophagus to the intestines for the digestive system to break down your food. Then you will use your legs(muscles) to go back to your bed and sleep. (don't copy this whole thing it is not complete and you must add stuff so it is complete im just giving you an idea or the structure of this essay)