Answer:
All living things are composed of cells.
Cells are the basic units of structure and function for living things.
All cells come from pre-existing cells. Also, organisms grow by “adding on more cells” NOT by increasing the size of their cells.
Explanation:
hope this helped!
Answer:
<u>Light microscope</u>:
- use a beam of light to produce magnified images
- can be used to examine living cells and tissues
<u>Scanning electron microscope</u>:
- use a beam of electrons to produce magnified images
- can be used to examine DNA
- can be used to examine cells
<u>Transmission electron microscope</u>:
- use a beam of electrons to produce magnified images
- can be used to examine DNA
- can be used to examine cells
Explanation:
Light microscope: is a commonly used microscope also known as compound microscope. Magnifies images from 40X upto 1000X. It uses ray of visible light to produce a magnified image. The light microscope can be used to view specimen of both living and dead cells or tissues. However, it doesn't give a detailed view of a specimen like electron microscope.
Scanning electron microscope: It uses electron beam as an illuminating source. It has a much higher resolving power than light microscope because it uses electrons instead of light. It magnifies object upto 500000 times the actual size. Internal structures can also be viewed. However, only dead specimen can be used because the beam of electrons can kill the cells. They are of two types:
- <u>Scanning electron microscope(SEM): </u>an electron beam passes over the specimen's surface and displaces electrons which are then focused on a screen to form an image. Images appear in 3-D
- <u>Transmission electron microscope: </u>electromagnets magnify the image by passing beam of electrons through a thin specimen. Images appear in 2-D
Answer:
Explanation:
When the phage enters a lysogenic cycle, it does not destroy the host but it manipulates the host's DNA and continues to reproduce. This is why the lysogenic cycle is also called nonvirulent phase.
Diastole is the relaxation phase of the cardiac cycle. It is the normal rhythmic dilation of the heart's valves. During this time, the valves start to gather blood inside of their chambers. There are two types of diastole that occur in the heart, and they are:
1. Ventricular diastole - this is the period where the ventricles are filling and relaxing.
2. Atrial diastole - the period in which the atria are relaxing.
This is a continuous cycle that occurs in the heart the moment a person is conceived until the person meets his/her death.
