Deoxyribonucleic acid (DNA) is the hereditary material that lies within the nucleus of all cells in humans and other living organisms. Most of the DNA is placed within the nucleus and is called nuclear DNA.
A chromosome is made up of two chromatids which are joined by the centromere. The chromatids separate from each other during mitosis to form two new chromosomes. The DNA making up a chromosome is dispersed as chromatin.
Under a microscope, chromatids look like little dots and chromosomes are lines.
        
             
        
        
        
Answer: This is called Monohybrid Experiment 
Explanation: Monohybrid Cross
P Generation	TT     *  	tt
  	Tall plants    	Dwarf plants
F1 Generation  
 T	T
t	Tt	Tt
t	Tt	Tt
In F1 generation;
There are 100% Tt Genotype and 100% Tall plant Phenotype
F2 Generation 
F1  	*  	F1
( Tt  	*  	Tt )
 T	t
T	TT	Tt
t	Tt	tt
In F2 Generation;
Genotype
There are 25% TT (homozygous dominant, tall plants).
50% Tt (heterozygous tall plants), and
25% tt (homozygous recessive dwarf plants).
This is how dwarf characteristics reappear in the second generation.
The Phenotype of F2 generation is 3:1  (Tall : Dwarf)
I have attached a document to this answer to facilitate effective understanding if there is anormalities in arrangement the Punnet Square.
 
        
             
        
        
        
The answer is True.............................
        
             
        
        
        
Answer:
True
Explanation:
Organic catalyst that increase the rate of biochemical reactions in the cells of living organism s are called enzymes.The are proteins with active sites which are specific to a particular  substrate, for enzyme-substrate complex and later enzyme product complex to formed.
They  act by lowering the activation energy  in the organic chemical reaction therefore increase the rate at which chemical reactions progress.
Hence when  the reactions are too slow,activation energy are high,because enzymes are not available to catalyze the reaction fixing the active sites with the the substrates.
 
        
             
        
        
        
Volcanic<span>eruptions, forest fires, pollen which can cause allergies, and ozone which is a pollutant made after lightning interacts with oxygen which can cause iritate the eyes, throat and lungs. 
hope I helped </span>