The overall structure is said to be a double helix composed of nitrogenous bases and the sugar backbone. It is also double stranded too
Answer:
Uncontrolled cell division can lead to the formation of masses of cells that can remain in a place called <u>primary </u>tumors or ones that can move called <u>metastatic </u>tumors.
Explanation:
The term primary tumor refers to the original tumor, a place where the tumor first appeared.
Metastatic tumors are tumors that appear in other organs and originate from the primary tumor. Tumor cells can break away from the primary tumor and travel to other locations in the body through the blood or lymph system and form new tumors. This is how metastatic tumors appear.
For example, a brain tumor is a primary tumor if it first appeared in the brain. A metastatic brain tumor is a tumor that appeared in another organ and then spread to the brain.
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.
A, but may not be correct
The graph is showing us the tide height in feet in the left side and the hight up and down.