Science Review 01

A bus is driving along a straight stretch of road. The bus driver, named Ray, has a cup of water resting on the dashboard: Suddenly Ray has to slam on the brakes. What is most likely to happen to the water in the cup?

• The water will stay horizontal.

• The water will spill over side 1.

• The water will spill over side 2.

• The water will spill but you cannot tell if it will spill at side 1 or side 2.

DNA is to be extracted from a blood sample and from cheek scraps. What is the reason why DNA will be found in both samples?

 

 

• They are the only places where DNA can be found.

• Both samples contain red blood cells.

• Both samples contain cells with nuclei.

• Both samples contain body fluids.

An important method of communication between cells is shown in the diagram. What is the chemical referred to in the diagram?

•  

       a hormone important in maintaining homeostasis

      

• an enzyme detected by a cell membrane receptor

     

   

• DNA necessary for regulating cell functions

      

   

• food molecule taken in by an organism

   

If a human system fails to function properly, what is the most likely result?

• a stable rate of metabolism

• a disturbance in homeostasis

      

• a change in the method of cellular respiration

• a change in the function of DNA

The police are asking all citizens of Mambajao, Camiguin to have a cheek scraping taken for DNA analysis. Here is a list of proposed safeguards for the people involved in this procedure.

 

Circle “Agree” or “Disagree” for each of these safeguards.

Which one of the following questions cannot be answered by scientific evidence?

 

• What was the medical or physiological cause of the victim’s death?

• Why was the victim stabbed many times?

• Is taking cheek scraps a safe way to collect DNA samples?

• Do all identical twins have the same DNA profile?

Which diagram shows that the particle arrangement is closely packed or arranged regularly?

•  

     Gas

   

       

    

•      Liquid

• Solid

•  Fluids

Which of the following describes the movement of liquids?

 

• They move about freely, but they stay close together because the forces of attraction between     
            them are quite strong, but not as strong as in solids

• The particles in liquids move a little bit. They vibrate in their fixed positions. The more energy the
            particles have, the faster and more strongly, they vibrate.

• Liquid particles move very fast, much faster than in solids and gas. The particles in a liquid possess a lot
           of energy.

• The particles in liquid do not move at all.

How do we compare the attraction between the particles of liquid and of gas?

•  

     The forces of attraction hold particles together in liquids while the forces between gas particles are very weak.

     

    

    

• They stay close together because the forces of attraction between them are quite strong, but not as
            strong as in solids while the forces of attraction between particles of gases are very weak

• The forces of attraction hold particles together. In liquids, these forces are strong

           enough to hold the particles firmly in position while the forces between particles of  gases are very weak

•   In liquid, the forces of attraction between them are quite strong, while the forces of attraction hold
           particles together in gases.

How does particle spacing, and motion affect the compressibility and density of substances in their different states (solid, liquid, gas)?

•  

  In solids, particles are closely packed with minimal motion, leading to high density and low

          compressibility.

    

   

    

   

• In liquids, particles are closely packed but move freely, resulting in moderate density and    
          compressibility.

•  In gases, particles are widely spaced with rapid motion, leading to low density and high compressibility.

• The compressibility of a substance is highest in solids because the particles are tightly packed.