Answer:
A
Explanation:
Hot air is less dense therefore it rises. Cold air is more closely packed therefore it is more dense. Less dense things rise while more dense things sink.
Weakly basic drugs behaves different from acidic drugs which is discussed below.
<h3><u>Explanation</u>:</h3>
Weakly basic drugs are those drugs which have an amine group associated with them. They are able to gain a proton to be come positively charged.
So drugs like quinine, ephedrine and aminopyrine which are basic got completely ionised in stomach.
The stomach can absorb those compounds which are lipid soluble. The acidic drugs like alcohols, Salicylic acid, aspirin, thiopental, secobarbital and antipyrine etc which are acidic gets absorbed by means of <em>diffusion</em> through the membrane.
But the basic drugs have charges on them which makes them lipophobic. So they cannot get absorbed through stomach. However weakly basic drugs sometimes get absorbed depending on their ionisation extent.
The rest goes to small intestine which has basic environment and there they gets absorbed via diffusion or facilitated diffusion.
They are living organisms in the ecosystem and make up part of the food chain.<span />
Plants have made a variety of reproductive adaptations to ensure the spreading and survival of their seed. A common example is the bright colors of many flowers. The purpose of this adaptation is to draw specific insects and birds that will visit the plant and distribute its pollen when they move on to the next plant.
Structural adaptations allow plants to live in specific environments, as is seen in the stark contrast between the roots of terrestrial plants, which are firmly rooted in the ground, and plants that float on the surface of bodies of water.
An example of a behavioral adaptation in plants is how certain desert plants have developed opportunistic behaviors that allow them to spring from dormancy to sudden reproductive activity during times of moisture and cool temperatures.
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