Cells and Organisation Flashcards
How do you calculate total magnification
Eyepiece lens x objective lens
Define the term resolution
Resolution is the ability to distinguish between two separate points in an image
What is the role of the nucleus
Contains DNA in the form of chromosomes. Contains the genetic code.
What is the role cytoplasm in a cell
This is where chemcial reactions take place
What is the function of the cell membrane
Controls what enters and leaves the cells.
What is function of the mitochondria is cells
This is the site of respiration.
Glucose + Oxyen –> Carbon dioxide + water vapour + ATP energy
Define the word ‘magnification’
Magnification is how much bigger an image is compared to it’s actual size.
Can be calculated by using the IAM triange.
Function of the cellulose cell wall
This is outer layer of plant cells. It is made of cellulose. It gives the plant strength and support.
Why are ribosomes needed in a cell?
Ribosomes are the site (location) where proteins are made.
Converting Units
nm / 1000 um / 1000 mm / 10 cm / 100 m / 1000 km
What is the function of chloroplasts in plant cells?
Chloroplasts contain a green chemcial called chlorophyll. It traps sunlight energy which is needed for photosynthesis.
What is the role of the vacuole
Is a space in the cytoplasm filled with cell sap. This is important for keeping the cells rigid to support the plant
1km = ?m
1000m
1m = ?cm
100cm
1cm = ?mm
10mm
1mm = ?um
1000um
1um =?nm
1000nm
Diffusion
The net random movement of particles from an area of high concentration to an area of low concentration.
Higher concentration gradient —>
Diffusion happens faster
Lower concentration gradient —>
Diffusion happens slower
Osmosis
The movement of water molecules from an area of low concentration to high concentration .
Where does osmosis happen
Across a partially permeable membrane.
What type of process is osmosis
It is a passive process
What two things are in a dilute solution
More water molecules Less solute (e.g.salt, sugar,ribena)
What two things are in a concentrated solution
Less water molecules More solute (e.g. salt, sugar, ribena)
Animal cell placed in a dilute solution is called…
Lysis
Animal cell placed in a concentrated solution is called…
Crenated
Plant cell placed in a dilute solution is called…
Turgid
Plant cell placed in a concentrated solution is called…
Plasmolysed
Active transport
The process by which molecules move from an area of low concentration to an area to an area of high concentration.
Active transport requires:
ATP energy
Carrier proteins in the cell membrane
