Breadth Paper

Question 1

Why di large organisms need an exchange system

Answer 1

large organism has a small SA:V
diffusion is too slow and distance is too long
cannot meet requirements of delivery of 02 to the tissues and removal of Co2 for metabolic demands

Question 2

What makes a more dense liquid

Answer 2

glycerol

Question 3

mag

Answer 3

21mm

Question 4

position of xylem and phloem

Answer 4

Phloem above

Xylem below - empty cells

Question 5

Experiment for measuring root hair density

Answer 5

microscope 
Graticule (calibrate)
count number of hairs per unit area 
repeat 
calculate mean 
divide by area to find density

Question 6

Relationship with water and root har density

Answer 6

further away less water available

- transpiration causes water loss

Question 7

Semi Conservative experiment

Answer 7

Tube 1 - contains light and heavy
Tube 2 - DNA only light/ strand of DNA is the template strand
Tube 10 - thicker as more DNA - light

Question 8

What does the standard deviation show

Answer 8

Spread of data around the mean

• if all results are similar to SD there is little variation; as one increases so does SD
• as increases repeatability increases

Question 9

Why is Rod As final length 5.0 cm and Rod Es 4.7

Answer 9

boiling damages cell surface membrane

- no osmosis out of A but water moves out of E

Question 10

How to set the colorimeter to zero and why

Answer 10

by placing a blank of distilled water to reset it to zero

- all values measured at the same standard