Pneumonia is caused by a variety of germs viruses, bacteria, fungi, and parasites.
Notes Some cells are visible to the unaided eye The smallest objects that the unaided human eye can see are about 0. That means that under the right conditions, you might be able to see an ameoba proteus, a human egg, and a paramecium without using magnification.
A magnifying glass can help you to see them more clearly, but they will still look tiny. Smaller cells are easily visible under a light microscope. Light microscopes use a system of lenses to magnify an image. The power of a light microscope is limited by the wavelength of visible light, which is about nm.
The most powerful light microscopes can resolve bacteria but not viruses.
To see anything smaller than nm, you will need an electron microscope. Electron microscopes shoot a high-voltage beam of electrons onto or through an object, which deflects and absorbs some of the electrons. Resolution is still limited by the wavelength of the electron beam, but this wavelength is much smaller than that of visible light.
The most powerful electron microscopes can resolve molecules and even individual atoms. Adenine The label on the nucleotide is not quite accurate. Adenine refers to a portion of the molecule, the nitrogenous base. It would be more accurate to label the nucleotide deoxyadenosine monophosphate, as it includes the sugar deoxyribose and a phosphate group in addition to the nitrogenous base.
However, the more familiar "adenine" label makes it easier for people to recognize it as one of the building blocks of DNA.
How can an X chromosome be nearly as big as the head of the sperm cell? Second, the DNA in a sperm cell is super-condensed and compacted into a highly dense form. Third, the head of a sperm cell is almost all nucleus.
Most of the cytoplasm has been squeezed out in order to make the sperm an efficient torpedo-like swimming machine. It has also been duplicated, so there are actually two identical copies stuck together at their middles.
A human sperm cell contains just one copy each of 23 chromosomes. A chromosome is made up of genetic material one long piece of DNA wrapped around structural support proteins histones.
Histones organize the DNA and keep it from getting tangled, much like thread wrapped around a spool.
PCR (short for Polymerase Chain Reaction) is a relatively simple and inexpensive tool that you can use to focus in on a segment of DNA and copy it billions of times over. Dr. P's Biology Teacher Resources. Need an Online Biology Textbook? Try this one. Or Kimball's Biology Text: This website is an accumulation of my science teaching resources for the past 15+ years. Enjoy our fun science facts for kids. Learn interesting earth facts, amazing chemistry facts, cool space facts, funny facts about animals and much more.
But they also add a lot of bulk. In a sperm cell, a specialized set of tiny support proteins protamines pack the DNA down to about one-sixth the volume of a mitotic chromosome.Pneumonia is a lung infection that can be caused by different types of germs, most commonly viruses. Read about symptoms and treatment.
Dr. P's Biology Teacher Resources. Need an Online Biology Textbook?
Pneumonia is a lung infection that can be caused by different types of germs, most commonly viruses. Read about symptoms and treatment. Greens - This includes materials such as grass clippings, vegetable waste, fruit scraps, and coffee grounds. Water - Having the right amount of water, greens, and browns is . Information about water, the water cycle, water pollution and how we use water for kids K - 6, with links to pages of related information.
Try this one. Or Kimball's Biology Text: This website is an accumulation of my science teaching resources for the past 15+ years.
This lesson helps to introduce the concept of viruses, what type of life forms they are, how they can be transmitted, how they affect humans and interfere with normal body functioning, and what our immune systems are.
|Eukaryotic Cell Organelles||Sodium hydroxide solution 0.|
|The water cycle||Genetics[ edit ] One of the strongest evidences for common descent comes from gene sequences. Comparative sequence analysis examines the relationship between the DNA sequences of different species,  producing several lines of evidence that confirm Darwin's original hypothesis of common descent.|
|Dr. P's AP Biology Page||Notes Some cells are visible to the unaided eye The smallest objects that the unaided human eye can see are about 0.|
|Viruses/Infectious Diseases: What’s Really Bugging You? - Science NetLinks||How does the body fight off a virus? The rhinovirus is one of the many viruses that can cause the common cold Viruses are infectious micro-organisms that require a living host to survive and multiply.|
|Water — kidcyber||We all need water to drink.|
Oil forms a thin layer on top of water and act like a lid on the surface and the water. Animals and plants living in the water can't breathe, the oil coats the feathers of water birds, and the fur of animals that swim in the water, causing them to become sick and, if there is a great amount of oil on their bodies, to die.
Apr 19, · Viruses are infectious micro-organisms that require a living host to survive and multiply.
When one enters your body, it invades and takes over cells, . Evidence of common descent of living organisms has been discovered by scientists researching in a variety of disciplines over many decades, demonstrating that all life on Earth comes from a single initiativeblog.com forms an important part of the evidence on which evolutionary theory rests, demonstrates that evolution does occur, and illustrates the .