Answer:
The correct answer is D)RNA polymerase
Explanation:
In DNA replication many enzymes and proteins are required to replicate a DNA template. For initiation of DNA synthesis the two DNA strands must be separated which is done by helicase.
Then primase adds short nucleotide sequence and initiate DNA replication. After that DNA polymerase acts and adds nucleotide at the 3' end of growing DNA strand. Ligase is the enzyme that joins the two Okazaki fragments that are created in the lagging strand.
RNA polymerase is not required in DNA replication and it works in transcription therefore the correct answer is RNA polymerase.
<span>10% rule (efficiency between trophic levels): limits how long an ecosystem's food chain can be
Predator/prey
cost benefit analysis (i.e. foraging) -- cost is risk of being eaten or
killed along the way, benefit is energy/nourishment obtained: limits
distribution of predator v. prey
Immigration/Emigration with other populations and ecosystems
Island
biogeography: size of land and distance from another
population/ecosystem (mainland): limits population size and variability
on island</span>
Answer:
Explanation:
The geologic time scale (GTS) is a system of chronological dating that relates geological strata (stratigraphy) to time. It is used by geologists, paleontologists, and other Earth scientists to describe the timing and relationships of events that have occurred during Earth's history.
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
