Answer:
most likely silt.
Explanation:
its not humus cause humus is sticky. its not sand cause when sand is wet its very gritty and hard. its not gravel because gravel is gritty. hope this helped
 
        
                    
             
        
        
        
Answer:
The overall function of light-dependent reactions, the first stage of photosynthesis, is to convert solar energy into chemical energy in the form of NADPH and ATP, which are used in light-independent reactions and fuel the assembly of sugar molecules.
Explanation:
 
        
             
        
        
        
Short-term memory holds information for 15 to 25 seconds and stores it according to its meaning rather than just as mere stimulation. However, it is not really true that short-term memory can be retained only for this short amount of time. It has been shown in different studies that it can be held even longer. 
        
             
        
        
        
Answer:
prokaryotic cells do not have a nucleus or membrane bound organelles.They also have small rings of double-stranded extra-chromosomal DNA called plasmids.
 
        
             
        
        
        
Answer:
true
Explanation:
Cerebrospinal fluids  is a  colorless fluid  that is secreted in the choroid plexus,and  circulates in the ventricles system  and sub -aranchinoid space  of the brain and spinal cord. its provides nutrients  to the surrounding  neurons, cushions the effects of trauma, pressure, acts as buffer and provides protection through immune  system .
it plays a vital role in regulating  blood flow, through a process called cerebral auto regulation,This is needed to maintain efficient cerebral blood flow of oxygen and other metabolites, and withdraw of metabolic wastes from the brain. 
in order to analyze it to diagnose some neurological diseases  its sample is usually taken out in a process called lumbar  puncture.