Plant cell have cell wall and animals cell don’t have
Plant cell have plastids and animal cell don’t have 
        
             
        
        
        
<span>The answer is : Both have true necks, while eusthenopteron has no neck.  </span>We know that tiktaalik is more closely related to acanthostega than it is Ichthyostega  eusthenopteron because Tiktaalik and Acanthostega both have true necks while eusthenopteron has none.
        
             
        
        
        
Answer:
This experiment proved that DNA replicated semiconservatively; half the original polynucleotide is conserved in each of the two copies
Explanation:
Semi-conservative mode of replication means that the two strands of DNA unwind from each other, and each of themacts as a template for synthesis of a new, complementary strand. As a result, two formed DNA moleculesc ontain one original strand and one new strand.
Meselson and Stahl experiment showed this model by labeling the DNA of bacteria across generations using isotopes of nitrogen ( patterns of DNA labeling showed the mode of replication).
 
        
                    
             
        
        
        
Answer:
A ribosome is made up of two basic pieces: a large and a small subunit. During translation, the two subunits come together around a mRNA molecule, forming a complete ribosome. The ribosome moves forward on the mRNA, codon by codon, as it is read and translated into a polypeptide (protein chain).
Explanation:
 
        
             
        
        
        
Remember that a controlled variable is a variable that stays the same thoughout the experiment.
it wouldn't be a. because two different wires were used
the final length of the wax would be your dependent variable, so it wouldn't be c.
the thermal conductivity is the independent variable so it isn't d.
the original length of the wax was the same for both.
So B is your answer.