Biology Prac Questions.

Year 11 Biology Unit 1 Outcome 1 Week 5 Quiz

  Question 1 Write a complete balanced equation for respiration. Question 2 Write a complete balanced equation for photosynthesis.

Question 3

a) Name the compounds that make up structures of A and B.

Simple diffusion and active transport are two ways in which movement can occur across a cell membrane b) Describe one difference between diffusion and active transport.

A cell from a marine plant was placed in sea water. Ion concentrations in the cytosol of the cell were measured over time and compared with the concentrations of the same ions in the surrounding sea water. The readings remained constant over the period of the experiment and are given in the following table. Substance analysed Cytosol Sea water Ion concentration (mg/litre) chloride Potassium 0.62 0.50 0.62 0.01

c) Which type of ion, chloride or potassium, is moved into the cell of the marine plant by active transport? Explain your answer.

Question 4 It is possible to dissolve and hence remove the outer hard shell of a hen’s egg. This leaves just the cell membrane undamaged and the cell contents intact. Shells were removed in this way from several eggs and each egg was laced in one of three different solutions. Solution 1 – distilled water Solution 2 – 0.5M sucrose Solution 3 – 1.5M sucrose The weight of the eggs was recorded at regular time intervals over one hour. The results are presented below.

a) Explain why there is a difference between the results of eggs placed in distilled water and eggs placed in 0.5M sucrose.

b) What conditions would an egg show neither an increase nor a decrease in weight?

c) A plant cell (drawing A) was placed in 1.5M sucrose. Draw in the space provided, the appearance of the cell after 3 hours in the sucrose.