Answer:
1. The correct answer would be A) allow you to view living cells, while electron microscopes do not.
There are many advantages of light microscope over electron microscope such as:
- It is easy to use as compared to the electron microscope.
- It enables us to view both alive as well as dead specimen whereas electron microscope can be used to view dead specimen only.
- Light microscopes are much cheaper and have much lower maintenance cost as compared to the electron microscope.
2. The correct answer would be C) scanning electron microscope
Scanning electron microscope or SEM is a type of electron microscope which is used to observe surface topography and composition of the specimen. It can achieve resolution of up to 1 nanometer.
3. The correct answer would be 400x
The total magnification of the microscope can be calculated by multiplying the powers of the objective lens and that of the eye lens.
Thus, the magnification of the specimen would be 40*10 = 400x.
Bacteria is a unicellular organism which can multiply very fast by binary cell division.
To get a number of divisions required for cell division: you can use the formula: 2
= number of bacteria
To get 256 bacteria:
2
= 256 (you can solve this equation by a calculator)
so:
n = 8 generations
With this formula the first bacteria is taken into consideration since 1 bacteria gives two, then the two give four, then eight, 16...
When a neuron carries the electrical potential of -70 millivolts, it is in the state called RESTING POTENTIAL. At the resting stage of the neuron, the inside of the neuron is 70 millivolts less than the outside. At this stage, there are more sodium ions outside the neuron and more potassium ions inside the neuron.
The population of the ground squirrels will be limited by the population of the hawks. The population of the hawks, thus, will be a limiting factor for the population of the ground squirrels. The Hawks are the birds of prey that feeds on squirrels. With the increased number of hawks in the same area as them will put these squirrels in danger. The population of the tree squirrels, however, will have no affect on the population of the ground squirrels. The genetic variability and breeding season are not limiting factors for their population either.
Hence, the correct answer is 'option B - a population of hawks'.
<span>In order to find the value of "a" and "b", first of all perform the multiplication in the parenthesis.
Thus
(3.5x1016) = 3556
and
(2.2x1010) = 2222
As per question;
(3556)x(2222) = 10 axb
By dividing both sides by "10"
we get
(3556)x(222.2) = axb
or
(355.6)x(2222) = axb
by comparing both sides of the equation,
we get that a = 3556 and b = 222.2
or
a = 355.6 and b = 2222
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