1. Animals
2. Plants
3. Virus
4. Prokaryote
Reflecting telescopes
Telescopes that use lenses are called refracting telescopes. The other type uses mirrors to focus the light of the image. These telescopes are called reflecting telescopes. Refracting telescopes use lenses to bend the light to a specific focal point such that the object will be magnified to the viewer.
light microscope
Optical instruments are based on optics. They use mirrors and lenses to reflect and refract light and form images. The light microscope and telescope use convex lenses and mirrors to make enlarged images of very tiny or distant objects. A camera uses a convex lens to make a reduced image of an object.
Refracting telescopes use lenses to focus the light, and reflecting telescopes use mirrors. I'll talk first about refracting ones. Refracting telescopes work by using two lenses to focus the light and make it look like the object is closer to you than it really is. Both lenses are in a shape that's called 'convex'.
the reflector telescope uses a mirror to gather and focus light. All celestial objects (including those in our solar system) are so far away that all of the light rays coming from them reach the Earth as parallel rays. Because the light rays are parallel to each other, the reflector telescope's mirror has a parabolic shape. The parabolic-shaped mirror focusses the parallel lights rays to a single point. All modern research telescopes and large amateur ones are of the reflector type because of its advantages over the refractor telescope.
Advantages
Reflector telescopes do not suffer from chromatic aberration because all wavelengths will reflect off the mirror in the same way.
Support for the objective mirror is all along the back side so they can be made very BIG!
Reflector telescopes are cheaper to make than refractors of the same size.
Because light is reflecting off the objective, rather than passing through it, only one side of the reflector telescope's objective needs to be perfect.
Disadvantages
It is easy to get the optics out of alignment.
A reflector telescope's tube is open to the outside and the optics need frequent cleaning.
Often a secondary mirror is used to redirect the light into a more convenient viewing spot. The secondary mirror and its supports can produce diffraction effects: bright objects have spikes (the ``christmas star effect'').
hope this helped!
Answer:
increases in crop productivity brought about by genetic engineering can help relieve problems faced by farmers by decreasing the losses caused by pests, disease, weeds,
Explanation:
The reason why sharks can swim fast is that unlike most fish, sharks have tails that are not horizontally symmetrical . Instead , the top of a shark's tail protrudes further back than the bottom , giving the shark lift while swimming and making it "spring" forward at speed.
Most fish make a single water "ring" that moves backward at the end of their tail's stroke but sharks are thought to produce two rings because of their asymmetrical tail which bespeaks a more efficient propelling action.
It has also been discovered that sharks can raise the tiny teeth-like structures called placoid scales on their skin to create tiny wells across the surface of their skin which reduces drag just like the dimples on a golf ball, thus enabling the shark move forward faster.
I believe the answer would be something like... there is a drought which causes a decrease in water availability which would then cause the population to decrease. The same thing also happens with food. Hope this helps. :)
