The slight positive charges on the hydrogen atoms in a water molecule attract the slight negative charges on the oxygen atoms of other water molecules. This tiny force of attraction is called a hydrogen bond.
The test that they can use in differentiating the gypsum and
quartz which are considered to be minerals is the mineral test. The mineral
test can differentiate the hardiness of the minerals, as well as their;
acidity, magnetism, streak, specific gravity and even their tenacity.
Answer:
This is antibiotic resistance. It occurs with over use of antibiotics.
When antibiotics are over used, likely targeted bacteria are being killed constantly even in absence of an infection. However, few bacteria may resist the antibiotics effects(selective pressure) , and therefore survived. If these resistant bacteria who were able to survive the selective pressure reproduce, they pass the resistant trait/ gene into their offspring.
Therefore with continuous exposure to antibiotics, they will resist the antibiotics effects(selective pressure),and thus reducing the effectiveness of antibiotic treatments with subsequent application.
Explanation:
The first one, ii. Natural selection and the formation of inseticide resistant insects or antibiotic resistant bacteria.
This can be explained in very simple way. As we all know, natural selection works in a way that only that adapted living beings are going to survive through a specific environment, whether it's because they can grab their food without too much work, or even that they can adapt to the weather. When we use inseticide, we are killing lots of non-resistant insects, and what's left are those that are resistant to this inseticide, and they'll reproduce again, and again we'll go through the same process, but remember, this insect is now stronger and more resistant that before.
The second case, iii. speciation and isolation give three examples how it may occur.
Well. the allopatric speciation and isolation will happen when theres a geographic barrier between one species. This one then is divided into two diffent habitats, but what can divide than could be a mountain, a tree, a river, a rock, anything. And this could be too called as a geographic isolation, because in this new environment, species are going to develop in a different way.
Hubble’s law
the farther they are the faster they are moving away from Earth.
