Pracs pt 4 Flashcards
How is osmosis investigated? 2
Observing effect of osmosis in plant cells
Can find out water potential (ψ) of plant using standardised sugar/salt solutions
What is one method to measure osmosis in potatoes? 2
Observe changes in mass of potato chips when left to stand in different concentrations of salt solutions
Standard salt solution will be supplied & will have to perform simple dilution to create different concentrations
What are the features of low power plan diagrams? 4
Features are just outlines of different tissues visible in an organ
Individual cells aren’t drawn
proportions & relative thickness of tissues are represented accurately
Eyepiece graticule can be helpful in judging proportions
What are the main features of high power plan diagrams? 3
Individual cells are shown as a small cluster of 3-5 cells
Cell walls are drawn in plant cells as 2 lines
Nucleus is drawn as a circle or oval and not coloured
What are the rules for plan diagrams? 5
Clear, solid lines
No shading/colouring
Show overall shape & proportions
Take up as much space as possible
Draw only what you see
What are the rules for labeling plan diagrams? 5
Use a ruler for lines
one end should touch part being labelled
No arrows
don’t cross label lines
Labels must be written horizontally
How can you see the difference between xylem and phloem when drawing a plan diagram? 2
Phloem usually stained green
Xylem usually stained red with thicker walls
How can you identify parenchyma when drawing a plan diagram?4
It’s a type of tissue that’s usually outside the vascular bundle
Has thin cell walls
nuclei may be visible
Cortex us mainly made up of parenchyma tissue
How can you identify collenchyma when drawing a plan diagram?2
Slightly thicker walls and is used for support
Usually found in stem & midrib of leaves
How can you identify the endodermis when drawing a plan diagram?
It’s a layer inside the organ that surrounds the vascular bundle
How can you identify the schlerenchyma when drawing a plan diagram?3
Usually appears red
has lignified walls
provides extra strength to stem
Why are chloroplasts arranged roughly in lines towards outside edge of cells?
Large permanent vacuole pushes chloroplasts to edge of cell
Maintains light availability for chloroplasts
How many layers of phospholipids are in a double membrane?
4
What makes chloroplasts appear green?
chlorophyll
What are the rules for comparative tables?5
Table is lined in pencil, writing is in ink
Each row & column needs a heading
Have column for feature under comparison on left side
Headings must match image/specimen labels exactly
Remember basic visible features
