Answer:
Following are the two types of living things that biologists could study:
1) Animals
2) Plants
Explanation:
As we know plants and animals are the most important organisms. Animals has further categories of living things are on land:
1) Birds
2) Mammals
3) Reptiles
4) Amphibians
Fishes are not included because they are in water but not on land.
The hind legs, I believe. That's why they are longer and stronger.
RNA is single-stranded while DNA is double-stranded.
RNA contains uracil while DNA contains thymine.
RNA has the sugar ribose while DNA has the sugar deoxyribose.
Answer:
Transmission electron microscope (MET): allows sample observation in ultra-thin sections. A TEM directs the electron beam towards the object to be increased. A part of the electrons bounce or are absorbed by the object and others pass through it forming an enlarged image of the specimen. To use a TEM, the sample must be cut into thin layers, not larger than a couple thousand thousands of angstroms. A photographic plate or a fluorescent screen is placed behind the object to record the enlarged image. Transmission electron microscopes can increase an object up to a million times.
A scanning electron microscope creates an enlarged image of the surface of an object. It is not necessary to cut the object into layers to observe it with an SEM, but it can be placed in the microscope with very few preparations. The SEM scans the image surface point by point, unlike the TEM, which examines a large part of the sample each time. Its operation is based on traversing the sample with a very concentrated beam of electrons, similar to the scanning of an electron beam on a television screen. The electrons in the beam can disperse from the sample or cause secondary electrons to appear. Lost and secondary electrons are collected and counted by an electronic device located on the sides of the specimen. Each point read from the sample corresponds to a pixel on a television monitor. The higher the number of electrons counted by the device, the greater the brightness of the pixel on the screen. As the electron beam sweeps the sample, the entire image of it is presented on the monitor. Scanning electron microscopes can enlarge objects 200,000 times or more. This type of microscope is very useful because, unlike TEM or optical microscopes, it produces realistic three-dimensional images of the object's surface.
Your "Digestive System" breaks down food into molecules that are then absorbed into your body.
