sac 1 bio

Question 1

permeable :
inpermeable:

Answer 1

• the cell membrane is permeable to water
• the cell is inpremeable to sugar becasue it is a large molecule that needs facilitatated diffusion to pass through

Question 2

process of transport in the two pracs

Answer 2

osmosis is diffusion of water molecules from a high water/low solute concentration to low water/high solute concentration

Question 3

aim experiment 1: onion

Answer 3

the aim of this investigation is to observe the change in shape of the onion cells after placing it in different solute concentration

Question 3

1experiment one IV, dv, cv onion

Answer 3

IV: solution concentration
DV: influence the size and shape of onion cells
CV: the concentration of sucrose, distilled water, the onion

Question 4

experiment two IV,DV,CV

Answer 4

IV: the concentration of solute in potato
DV: change in potato mass
CV: distilled water, the size of the ruler, the time potato were left in sucrose solution

Question 4

aim experiment 2: potato

Answer 4

the aim of this investigation is to measure the effect of the concentration solution has on the potato via osmosis

Question 4

which experiment has the best hypothesis: 2nd one

Answer 4

the second experiment because it states the overall iv and how it effects the dv with a directional reasoning

Question 5

Q3A) first cell
second cell

Answer 5

1m sucrose
distilled water

Question 6

why onion cell is not bursting

Answer 6

the onion cells are not bursting because of the cell wall. cell wall can dilute hypotonic media and prevent bursting of cells

Question 7

onion cell diagram

Answer 7

dv Y: percentage of change in potato (increase/decrease) %
Iv x: concentration of sucrose in solution (%)
Title: the change of mass in potato after increasing solution

Question 8

overall trend in experiment 2

Answer 8

the overall trend in experiment 2 shows the decrease of the mass in potato from its initial mass of 4% in distilled water to 2% in 5% of sucrose solution

Question 9

which sucrose concentration did not have change in mass of potato

Answer 9

there was no change in the concentration of sucrose solution at 6-7% of because it reached its optimal level

Question 10

describing experiment two is better

Answer 10

it was easier to describe the trend for experiment two because there was more reliability. experiment two had scale to determine the measurement which gave accurate results however, experiment one was based of person perception that gave inaccurate results

Question 11

similarity in both experiments

Answer 11

both experiments used plant cells

Question 12

differences between two experiments

Answer 12

1: the onion was peeled with our hands
2: where else a cork borer was used to cut the potato

Question 13

experiment 2: limitations potato

Answer 13

limitations: the cutting for the potato into 3cm lead to inaccurate results since it was not precise
improvements: a machine that could cut an precise and accurate size of the potato

Question 14

which experiment is more effective two reasons

Answer 14

experiment 2 because experiment two had more accurate results since it had scales to measure the results. Another reason is because there was more precision since there was precise measurements of concentration used