Cells Flashcards
How do you calculate total magnification?
Eye piece 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 chemical reactions take place
What is function of the mitochondria in 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.
What is the IAM triangle
I= image
A=actual
M= magnification
What is a eukaryotic cell?
Eukaryotic cells all have a cell membrane, cytoplasm, and genetic material that is enclosed in its nucleus. The genetic material is called DNA and this forms structures called chromosomes that are contained within the nucleus. All animals, plants, fungi and protasti are eukaryotes.
What is the nucleus?
The nucleus contains genetic material, the genetic material controls what the cell does.
What is the cytoplasm?
The cytoplasm is where most of the chemical reactions happen
What is the cell membrane
The cell membrane controls what goes in and out of the cells.
What are mitochondria
Mitochondria is where most aerobic respiration happens. Respiration transfers energy that the cell needs to work.
What are ribosomes?
Ribosomes are where proteins are made in the cell
What is a cell wall?
A cell wall is made of cellulose it supports the cell and strengthens it.
What is a permanent vacuole?
A permanent vacuole contains cell sap
What are chloroplasts?
This is where photosynthesis happens, photosynthesis makes food for the plant.
What are prokaryotic cells?
Prokaryotes are single cell living organisms that have been around for millions of years, they are older than eukaryotic cells. An example of this cell is bacteria they normally have a cytoplasm and a cell membrane surrounded by a cell wall, but the cell wall does not contain any cellulose. It has a nucleus, the bacteria chromosome is a single DNA loop found free in the cytoplasm.
What is a dilute solution?
A liquid that is weakened by adding something to it e.g. water
What is a concentrated solution?
It is the substance that is the strongest in the solution
What is diffusion?
Diffusion is the net random movement of particles from an area of higher concentration to an area of lower concentration.
How does the rate of diffusion work?
The larger the surface area of the membrane, the faster the rate of diffusion is to where there’s a lower concentration.
What is osmosis?
Osmosis is the movement of water molecules across a partially permeable membrane from a less concentrated solution to a more concentrated solution.
What does lysis mean?
When an animal cell becomes too dilute in a solution they call it lysis.
What does crenated mean?
When an animal cell becomes too concentrated with a solution they call it crentated
What does the word turgid mean?
When a plant cell becomes too dilute with a solution e.g. they have been watered too much, they are called turgid.
What does plasmolyzed mean?
When a plant cell becomes too concentrated with a solution they call it plasmolyzed
What is active transport?
Active transport is the process were a substance needs to be absorbed from a lower concentration to a higher concentration against the concentration gradient.
What is surface area to volume ratio?
Surface area is the perimeter of a shape and volume is the inside of the shape therefore the larger the shape the smaller the surface area to volume ratio is.
Converting units
Remember to divide to get the units to become a greater measurement
Remember to times to get the units to become a smaller measurement
Interphase in the cell cycle
- Interphase
This when the cell prepares to divide: the cell increases in size.
DNA replicates and organelles (mitochondria and ribosomes) also replicate
Mitosis in the cell cycle
Chromosomes line up along the centre of the cell.
Chromosomes get pulled to opposite ends of the cell.
Nucleus divides.
Cytokinesis in the cell cycle
Cytoplasm and cell membrane divide.
2 identical cells are formed
