<span>Bacteria are tiny. A typical bacterial cell is just a few micrometres across (a few thousandths of a millimetre). The structure of a bacterial cell is different to an animal or plant cell. For example, they do not have a nucleus but they may have a flagellum. This is a tail-like part of the cell that can spin, moving the cell along.A unicellular organism is a living thing that is just one cell. There are different types of unicellular organism, including:
bacteria
protozoa
unicellular fungi
You might be tempted to think that these organisms are very simple, but in fact they can be very complex. They have adaptations that make them very well suited for life in their environment.Protozoa are unicellular organisms that live in water or in damp places. The amoeba is an example of one. Although it is just one cell, it has adaptations that let it behave a bit like an animal:
it produces pseudopodia (false feet) that let it move about
its pseudopodia can surround food and take it inside the cell
contractile vacuoles appear inside the cell, then merge with the surface to remove waste
You may be familiar with fungi from seeing mushrooms and toadstools. Yeast are unicellular fungi. They are used by brewers and wine-makers because they convert sugar into alcohol, and by bakers because they can produce carbon dioxide to make bread to rise.
Yeast have a cell wall, like plant cells, but no chloroplasts. This means they have to absorb sugars for their nutrition, rather than being able to make their own food by photosynthesis
Yeast can reproduce by producing a bud. The bud grows until it is large enough to split from the parent cell as a new yeast cell.</span>
ANSWER: POPULATION ECOLOGY
EXPLANATION:
The scientific field that deals with populations (i.e all individuals of a single species inhabiting a community) and how they interact with their extrinsic environment, is referred to as POPULATION ECOLOGY.
Thus, it's categorized under population ecology, because the research depicts how the number of individuals (beetles) in a population changes in time and the gross impact on their number decrease and loss of all the individuals (extinction) over a period of time.
Answer: The estimated population is 1250 mice
Explanation: The method use was marked and recapture, in which individuals are marked in the first capture and after some time biologist trap a new group of individuals that can be or not marked
Whit this data is possible to estimate the size of a population applying the Peterson method but is important to make some considerations such as:
1. All indivuals have the same probability to be capture
2, The population remain constant in terms of birth and death rate.
Taking this into account, the formula that allows to determine the size of the population is:
N=CM / R
where N is the size of the population, C is number of indivuals trapped in recapture, M is number of individuals marked in the first capture and R is the number of marked animals trapped in recapture
In this case:
N = 250 * 200 / 40 = 1250