Answer:
years
Explanation:
Given-
Half life of 
C 
years
As we know -
Where
Mass of radioactive carbon after a time period "t"
initial mass of radioactive carbon
radioactive decay constant
time
First we will find the value of "k"
On solving, we get -
Now, when mass of 14C becomes 
% of the plant material on earth today, then its age would be
years
<span>A single gene can only influence a single trait is a FALSE
statement. Genes is a factor to the inherited traits. In human genetics there
is dominant trait that a person can inherit from their parents. Diseases and
disorders can be passed through genes by the family.</span>
"Memory Cells", are cells responsible for remembering what and how to fight off a specific pathogen. When a memory cell is produced for a specific pathogen, you are granted long lasting immunity.
The answer is true.
<span>Antigens are molecules capable to induce an immune response, "targeted" by antibodies. Antigens are usually proteins, peptides, or polysaccharides but they can combine with lipids and nucleic acids and form more complex antigens (lipopolysaccharide). Usually, antigens are exogenous (foreign substances), but sometimes are part of the host itself (in an autoimmune disease). All of them contain an epitope which is a part of an antigen that can be recognized and bound by an antibody.</span>
