7. (a) (i) Give a reason why living cells need water - Leaving Cert Biology - Question 7 - 2020
Question 7
7.
(a) (i) Give a reason why living cells need water.
(ii) State a function of a selectively permeable membrane.
(b) Answer the following questions in relat... show full transcript
Worked Solution & Example Answer:7. (a) (i) Give a reason why living cells need water - Leaving Cert Biology - Question 7 - 2020
Step 1
Give a reason why living cells need water.
96%
114 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
Living cells need water for a variety of reasons, including temperature regulation, transport of nutrients and waste, and as a solvent for biochemical reactions. In essence, water is vital for maintaining cellular homeostasis.
Step 2
State a function of a selectively permeable membrane.
99%
104 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
A selectively permeable membrane allows the passage of some molecules while restricting others, thereby maintaining the internal environment of the cell.
Step 3
Name one piece of apparatus and one solution you used during your investigation.
96%
101 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
One piece of apparatus used was a test tube, and the solution was a sugar solution.
Step 4
What control was used?
98%
120 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The control used in the investigation was boiled potato or distilled water in a visking tube.
Step 5
What did you use as a selectively permeable membrane?
97%
117 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
I used 'visking tubing' or potato tissue as the selectively permeable membrane.
Step 6
What information did you record at the start of the investigation?
97%
121 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
At the start of the investigation, I recorded the mass or volume of liquid in the test tube before the experiment.
Step 7
What did you observe during the investigation that showed osmosis had occurred?
96%
114 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
I observed an increase in mass and more liquid in the test tube, indicating that osmosis had occurred, as water moved from an area of high concentration to low concentration.
Step 8
What did you conclude from your observations about the direction of water movement during osmosis?
99%
104 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
I concluded that during osmosis, water moves from an area of high water concentration to an area of low water concentration.
Step 9
Name a simple food preservation technique linked to osmosis.
96%
101 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
A simple food preservation technique linked to osmosis is pickling, where high salt or sugar solutions are used to draw water out of cells, thus preserving the food.
Join the Leaving Cert students using SimpleStudy...
