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.
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.
To find out the magnification
Magnification= image size / actual size
To find out the actual size
Actual size= image size / magnification
To find out the image size
Image size= magnification x actual size
What is diffusion?
Diffusion is the movement of substances from a place of high concentration to a place of low concentration.
Diffusion is a passive process
E.g O2 diffuses out of the lungs and into your blood stream
What is osmosis? How is it related to Diffusion?
Osmosis is a different type of diffusion but instead of many different substances it is to do with water molecules.
The water molecules move from an area of high concentration to areas of low concentration.
Carbohydrates
Carbohydrates are made up of long chains of simple sugars For example starch g-g-g-g-g-g-g-g-g-g G= glucose There are three types of carbohydrates: Sugar= gives us energy Starch= gives us energy Fibre= prevents constipation
Proteins
Proteins help your growth
And proteins also help repairing of body tissues
They are made up of long chains of amino acids
Lipids
Lipids are also called Fats
Lipids help you keep warm (insulation)
And they can also give us energy
Lipids are made up of 1 molecule of glycerol and 3 attached fatty acids
Types of specialised cells
Sperm cells Red blood cells White blood cells Skin cells Egg cells
Two types of unspecialised cells/ Stem cells=
Adult (tissue) stem cells
Embroyonic stem cells
Stem cells
Stem cells can replicate many times.
Has the potential to become specialised
Embryonic cells
Are stem cells found in embryos they are known as embroyic stem cells
And can develop-into almost every cell type under he right conditions in a lab
Adult stem cells
Found in adult tissues such as bone marrow brain and muscle and liver cells. These can only change into the same type of cells as the tissue so if they come from liver cells they become liver cells.
Tissue
Formed by a lot od similar cells working together to preform the same function
