Lactase refers to an enzyme that can dissociate lactose sugar into glucose and galactose. This enzyme plays an important role in the digestion of milk that comprises high lactose sugar. In case, if a mutation occurs in the gene codon of lactase, then two possibilities can take place. These are as follows:
1. Loss of mutation: In this case, the person becomes lactose intolerant because of mutation in lactase gene codon. Due to this, there is low mRNA expression and thus low production of the enzyme lactase. This is also known as lactase non-persistent phenotype.
2. Gain in mutation: In this case, the person gain an increase in mRNA expression of the lactase gene, thus more production of lactase takes place than usual. This kind of individual exhibits lactase persistent phenotype.
Answer:
James suffers from a condition called Duchenne muscular dystrophy.
Answer:
Gated ion-channels
Explanation:
These ion channels are protein molecules that act as a passageway which span across the cell membrane allowing the movement of ions from one side of the membrane to the other. They possess the ability to open and close in response to either chemical or mechanical signals.They possess a fluidic pore, which becomes available to ions after a conformational change in the protein structure has been activated causing the ion channel to open. Based on the stimulus to which they respond, ion channels are divided into three groups: voltage-gated, ligand-gated and mechano-sensitive ion channels. Channels responding to electrical (voltage-dependent ion channels), mechanical, or chemical (ligand-gated ion channels) stimuli open and allow rapid ion movement into or out of the cell, and this movement creates an electrical signals.
Answer:
d) A group that does not drink soda (caffeinated or decaffeinated) or other caffeinated beverages for 10 days
Explanation:
In an experiment, two groups exist as follows: experimental group and control group. Experimental group is the group that receives the experimental treatment (independent variable) while the CONTROL GROUP is the group that does not receive the experimental treatment.
In this experiment, the experimental treatment is the CAFFEINATED SODA (contains caffeine). Hence, the appropriate control group for this experiment will be the group that does not drink any soda (whether caffeinated or decaffeinated) or other caffeinated beverages for 10 days.