1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
alexgriva [62]
3 years ago
14

How many years did the precambrian era span

Biology
1 answer:
frozen [14]3 years ago
5 0

Answer: Precambrian, period of time extending from about 4.6 billion years ago (the point at which Earth began to form) to the beginning of the Cambrian Period, 541 million years ago.

Explanation:

i don't if this is want your looking for but hope it helps

You might be interested in
The sodium potassium pump is an active transport pump that uses energy to pump potassium into cells and sodium out of cells. Why
ss7ja [257]

Answer:

i think it is Na+K-ATPase

6 0
2 years ago
What is the difference between a control group and an experimental group?
Serjik [45]

Control Group: Group that is being controlled .This group doesn´t receive the treatment from the researchers

Experimental Group:Group that is being Experimented and that receives the testing

3 0
3 years ago
Read 2 more answers
Please help there’s 3 questions at the bottom left.
Zarrin [17]

please help there’s 3 questions at the bottom left.

8 0
3 years ago
1. Why it is important to to have appropriate amounts of calcium in the body?
coldgirl [10]

Answer:

Almost all calcium in the body is stored in bones and teeth, giving them structure and hardness. Your body needs calcium for muscles to move and for nerves to carry messages between your brain and every part of your body.

Sodium-Potassium Pump

Three sodium ions bind to intracellular sites on the sodium-potassium pump.

A phosphate group is transferred to the pump via the hydrolysis of ATP.

The pump undergoes a conformational change, translocating sodium across the membrane.

5 0
2 years ago
Like all enzymes, restriction endonucleases (REs) need to be handled very carefully to ensure that they do not denature. Which o
andriy [413]

Answer:

The correct answer is:  d. REs activity is best preserved by freezing the RE and thawing it out for brief periods of time as needed.

Explanation:

  • Restriction enzymes can be defined as endonucleases that can recognize specific nucleotide sequence in a DNA (Deoxyribonucleic acid) sequence and cause breakage of phosphodiester bond in the DNA at the target site. Hence, it has the capacity of cleaving a DNA sequence.
  • These are made up of proteins which are required to be present in the accurately folded conformation in order to function.
  • Any form of alteration in the three-dimensional structure of the protein induced due to physical, chemical, mechanical or physiological factors can cause denaturation of the protein which in turn can render the protein non-functional.
  • Freezing of restriction enzymes (REs) directly without the use of glycerol will cause the movement of water molecules within the proteins as well layering of water molecules on the protein surface.
  • At low temperature these water molecules change to ice crystals which can alter the conformation of the protein or can cause breakage of peptide bonds in the proteins by physical force.
  • This can cause the protein to get denatured and hence non-functional.
  • Hence, it is never advisable to preserve REs by freezing directly without glycerol.
  • Glycerol forms a layer around the protein molecules and prevents the protein molecules from coming into direct contact with the water molecules and hence prevents protein denaturation.
7 0
3 years ago
Other questions:
  • Mid-ocean ridges are underwater mountainous regions formed by the separation of ___________. A) tsunamis B) tectonic plates C) c
    13·1 answer
  • Energy can be _____ or _____,but can be refused
    8·1 answer
  • Hich of mr. helms' vital signs and lab values were abnormal?
    6·1 answer
  • The circulatory system works best with which other body system to supply the body’s cells with the nutrients they need?
    13·2 answers
  • Students were asked to identify the function of each part of the flower labeled
    15·1 answer
  • Any process that does not require oxygen is (blank answer here) . while any process that does require oxygen is ( Blank answer h
    10·1 answer
  • I need to know the steps on how to become a dentist, like what all do I need to do, what I should major in (the most important q
    8·1 answer
  • #5 Which statement is true in regards to DNA mutations? *
    6·1 answer
  • Plz help now I need it
    12·2 answers
  • Linnaeus classified organisms into two kingdoms. How was his system of classification impacted after the invention of the micros
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!