Answer:
C. antigen-antibody reactions
Explanation:
human blood group is determined by the presence of antigens on the red blood cells which are specific proteins.
so specific antibodies are used against these antigens to determine the type of blood group after the reaction.
Answer:
The correct answer would be gene flow.
Explanation:
Gene flow is explained as the transfer of genes from one population to another so there is an increase in their frequency of genes.
It is also called migration. The addition or loss of people can affect the frequencies of the gene pool even if no other evolutionary mechanisms working at the time.
Thus, the correct answer would be gene flow.
Gills would be the most common sense answer. I took the test and it was correct.
The correct choice is increases your heart rate and respiration.
Your sympathetic nervous system increases your heart rate and respiration when confronted with a stressful event.
sympathetic nervous system also mobilizes body for action, increases breathing and sweating, makes pupils dilated ad lastly decreases stomach's activity.
