Actively transport molecules across the cell membrane
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.
A model of a globe is a physical model. The limits are that the solar system is too big to be seen all at once. From the Tennessee science textbook, "Many years ago, scientists thought that Earth was the center of the universe and the sky was a blanket that covered the planet. Later through the observation, it was discovered that the objects you see in the sky are the sun, the moon ,stars, and other planets. This new model explained the solar system differently.
The creation of DNA fragments with ends that can join with other DNA is achieved by the use of restrictive enzyme analysis.
<h3>What are restriction enzymes?</h3>
They are enzymes utilized in genetic engineering or gene recombination technology to cut DNA at some specific points in other to have sticky ends.
The sticky ends DNAs are able to join with other DNAs using these ends. Another enzyme (Ligase) is utilized to join the DNA back once the desired DNA has been inculcated.
More on restriction enzymes can be found here: brainly.com/question/13944056
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One of the species dieing off.
