The first line of defence (or outside defence system) includes physical and chemical barriers that are always ready and prepared to defend the body from infection. These include your skin, tears, mucus, cilia, stomach acid, urine flow, 'friendly' bacteria and white blood cells called neutrophils.
Answer;
-Reproduction;
Explanation;
-Mitosis is a shape of cell division that outcomes in two daughter cells which might be genetically identical to every other and to the unique cell.In unicellular organisms together with micro organism, mitosis is a kind of asexual duplicate, making equal copies of a unmarried mobile.
- Single-celled or unicellular organisms use cell division as their method of reproduction. Mitosis is a type of asexual reproduction, making identical copies of a single cell. Cells make identical copies of themselves through mitosis.
Answer: D). Primary species have large numbers of offsprings, and climax communities contain species that have small numbers of offsprings.
An ecological succession is a process of gradual changes occurs in a biological community with respect to changes in the non-living abiotic factors (water, air and sunlight) and with respect to time until the ecosystem attains stability. Primary or pioneer species are the species which invade the previously barren and primitive landmass for their survival. These species make the environment suitable for the growth of other species. These grow and develop in the initial stages of succession. These species are simple organisms which reproduce asexually and produces large number of offsprings. Examples are lichen and moss. Lichen grows on the surface of rocks and acids released by them causes withering of rocks into soil which facilitate the growth of mosses and other plants. Climax community develops in an ecosystem after replacing many previously inhabiting species. Climax community develops in the end of the ecological succession. It contains species which are highly complex and uses sexual reproduction for the production of offsprings which are less in number as compared to those produced by pioneer species by asexual reproduction.
Answer:
The correct answer will be option-accurate and complete DNA replication.
Explanation:
The cell cycle of a cell is controlled by the internal checkpoints where the cell cycle halts until the favourable conditions appear. These checkpoints are G1 checkpoint, G2 checkpoint and M checkpoint.
The G2 checkpoint asses that the DNA replication has been completed, all the chromosomes have been replicated and the replicated DNA is not damaged. The cell cycle stops if the replicated DNA is found damaged.
Thus, option-accurate and complete DNA is the correct answer.
Answer:
Explanation:
An element only has <u>one</u> type of atom and cannot be broken down by chemical means.
Let's analyze the answer choices.
1. This has two types of atoms, so it cannot be an element. It has more than one type of atom.
2. This has two types of atoms that are bonded together. It cannot be an element because there is more than one type of atom and the bonds can be broken.
3. This has one type of atoms, so it is an element.
Therefore the best answer choice is 3.
