Objective Lenses: Usually you will find 3 or 4 objective lenses on a microscope. They almost always consist of 4x, 10x, 40x and 100x powers. When coupled with a 10x (most common) eyepiece lens, we get total magnification of 40x (4x times 10x), 100x, 400x, and 1000x. To have good resolution at 1000x, you will need a relatively sophisticated microscope with an Abbe condenser. The shortest lens is the lowest power, the longest one is the lens with the greatest power. Lenses are color coded and if built to DIN standards are interchangeable between microscopes. The high power objective lenses are retractable (ie 40xr). This means that if they hit a slide, the end of the lens will push in (spring loaded) thereby protecting the lens and the slide. All quality microscopes have achromatic, parcentered, parfocal lenses.
Explanation:
I don't know for sure if this is correct but hopefully it is( ꈍᴗꈍ)
If B and b are the two alleles , B + b = 1 and B ^2 +2 Bb + b ^2 = 1.
If 16% of mice are homozygous black , B ^ 2 =0 .16, meaning B = 0 .4 and b = 1 - 0. 4 = 0 .6 . Answer = Notice how you don't even need to know that 24% of the mice are heterozygous .
A vaccine is used to provide active acquired immunity to the host by supplying them with a biological preparation which is often made up of attenuated organism, its associated immunogenic particle, protein, DNA, etc.
Today there are vaccines available for a wide variety of diseases however there is no preventive vaccine for listeriosis.
Listeriosis is a disease caused by <em>Listeria monocytogenes</em> and it is a very serious disease often caused due to the consumption of contaminated food.
There is unavailability of a commercially available vaccine against listeriosis although a lot of research is underway to prepare a vaccine to reduce the mortality rate.
