Carbon dioxide and oxygen
With a light microscope one can view the nucleus and endoplasmic reticulum, large vacuoles etc
The resolution of a light microscope is dependent on the wavelength of light that is the main beam of illumination. Light has approximately 0.4 um (UV)- 0.7um (Infrared) wavelength. Organelles smaller than about 0.5 um will be difficult to discern with a light microscope.
With an electron microscope one can view, in addition, even the ribosomes and mitochondria, chromosomes, tubules etc.
An electron microscope can discern very minute details of a cell. This is because its resolution is dependent on the very small wavelength of a beam of electrons which is approximately 0.002 um (about 10,000 times powerful than a light microscope)
Exchange of gases in fish is very efficient because of: the large surface area of the gills. the large surface area of the blood capillaries in each gill filament. the short distance required for diffusion – the outer layer of the gill filaments and the capillary walls are just one cell thick.
Answer:
Antibiotics have helped in a speedy recovery for human illnesses over the past century.
Explanation:
Because anti biotics were not present centuries ago, many would get sick and even die. However, antibiotics work by affecting things that bacterial cells have but human cells don't. This helps to fight off the bacterial cells and fight infections and viruses, leading to a speedy recovery.
