KS4 Combined Science (Trilogy)  Homework 1
Q1.  The diagram below shows a human bone cell.

(a)     Label the cell structures A, B and C on the diagram above.
(3)
(b)     Which structure in the cell contains DNA?
Tick (✓) one box.
 
A		B		C		
(1)
(c)     A student used a microscope to view a cell.
The length of the image of the cell was 40 mm
The real length of the cell was 0.25 mm
Calculate the magnification of the image.
Use the equation:

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Magnification = ×_______________
(2)

(d)     Root hair cells are found on the roots of plants.  Root hair cells do not photosynthesise.
Give one structure found in a leaf cell, but not in a root hair cell.
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(1)
(e)     Which two structures are found in plant cells but not in animal cells?
Tick (✓) two boxes.
 
Cell wall		
Mitochondria		
Permanent vacuole		
Plasmid		
Ribosome		
(2)
(Total 9 marks)
Q2. The image below shows an epithelial cell from the lining of the small intestine.
 
(a)     (i)      In the image above, the part of the cell labelled A contains chromosomes.
What is the name of part A?
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(ii)     How are most soluble food molecules absorbed into the epithelial cells of the small intestine?
Draw a ring around the correct answer.
 
diffusion	osmosis	respiration	
(1)
(b)     Suggest how the highly folded cell surface helps the epithelial cell to absorb soluble food.
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(1)
(c)     Epithelial cells also carry out active transport.
(i)      Name one food molecule absorbed into epithelial cells by active transport.
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(1)
(ii)     Why is it necessary to absorb some food molecules by active transport?
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(1)
(ii)     Suggest why epithelial cells have many mitochondria.
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(2)
(d)     Some plants also carry out active transport.
Give one substance that plants absorb by active transport.
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(1)
(Total 8 marks)

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