Answer: 
Gas exchange
Explanation:
Gas exchange takes place in the millions of alveoli in the lungs and the capillaries that envelop them. As shown below, inhaled oxygen moves from the alveoli to the blood in the capillaries, and carbon dioxide moves from the blood in the capillaries to the air in the alveoli.
 
        
             
        
        
        
Ribosomal RNA (rRNA) associates with a set of proteins to form ribosomes. These complex structures, which physically move along an mRNA molecule, catalyze the assembly of amino acids into protein chains.
 
        
             
        
        
        
Answer:
Bio carbonate ions
Explanation:
The pancreas secrets an aqueous mixture ( water, digestive enzymes and bicarbonate ions) during digestion of food substances from the stomach into the duodenum to begin the process of absorption and assimilation.
The pancreatic duct are lined with duct cells. These are cells which secretes HCO3- ,into the aqueous mixture. This ion is basic. Therefore it  neutralizes the acidity of the  of  the chyme to  released from the stomach to enable the pancreatic enzyme to work.
The bicarbonate ions also prevent the walls of the pancreases from getting burnt by the effect if the acidity of the chyme.
 
        
             
        
        
        
Correct Completed  Questions; Susan, a 67 year old female is experiencing ataxia, or poor muscle coordination. Doctors perform a neurological exam and they find that Susan is not positive for the Romberg test. Describe what these findings suggest about the sources of Susan's ataxia.
Answer:s
In order to test for balance and positioning(proprioception)   as a measure of  neurological function, or to test level   of intoxication alcohol  during driving, Romberg test is usually conducted,which can be negative or positive.It is generally used to investigate the cause of loss of motor control in individuals.
Explanation:
A positive result  showed that her  ataxia was due to loss of positioning due to loss of  sensory from sensory neurons.However if negative as in the case of Susan, then it  is to due to abnormality/dysfunctions   in the cerebellum, and not due to loss of sensory functions,