Cell bio B1 Flashcards
What is the light microscopes maximum magnification and resolving power
Magnification to x2000
resolving power of 200nm
What is the maximum magnification of an electron microscope?
They can magnify up to about x2,000,000
Resolving power of 0.2nm
What is the Magnification equation?
Magnification = Size of image / Size of real object
What type of cell is an animal cell and what does it mean
An animal cell is eukaryotic meaning its genetic material (DNA) is enclosed in its nucleus
What is a nucleus?
Holds the genetic material of an organism
What is a cytoplasm
Its where chemical reactions take place
What is a cell membrane?
Controls molecules that enter + leave the cell
What is the mitochondria?
Aerobic respiration takes place here
What is a ribosomes function?
Sites of protein synthesis
and its the smallest organelle of an organism
What structures do plant cells have that animals dont?
Chloroplasts
Cell wall
Permanent Vacuole
What do chloroplasts do?
They contain chlorophyll and sites of photosynthesis
What is a cell wall ?
Made of cellulose and strengthens the cell
What is the permanent vacuole for in plants?
Its filled with cell cap to help the plant cell by giving it shape
What’s a prokaryotic cell?
A type of cell which doesn’t have a nucleus / doesn’t contain its genetic material in its nucleus
Instead, its genetic material is enclosed in the plasmid and single loop of DNA
Which is smaller prokaryotic cells
or eukaryotic cells?
Prokaryotic cells are smaller than eukaryotic cells
Give an example of a prokaryotic cell
Bacteria
What is animal cell specialisation?
When an animal cell has adaptations to carry out its particular function
What do scientists call cells that become specialised?
Differentation
How are sperm cells are specialised (adapted)
Long streamlined tails for swimming
Lots of mitochondria to provide it for swimming
Contains digestive enzymes to break through the outer layer of an egg cell
What do nerve cells do?
And how are nerve cells specialised?
Dendrites - increase the surface area so other nerve cells can connect easier
Mylin - Insulates the axon to speed up the transmission of nerve impulses
Axon - carries electrical impulses from one part of the body to another part of the body
Synapses - Junctions/gaps allowing impulses to pass from one nerve to the other
How are muscle cells specialised (adapted)?
Muscle cells have protein fibres to change their length / allowing the cells to get shorter
They have mitochondria to provide it with energy for muscle contraction
How are root hair cells specialised?
Hairs on root hairs increase the surface area so it can absorb water + dissolved minerals more effectively
Lots of mitochondria to provide energy for active transport
How are xylem specialsied?
Contains the chemical lignin to support the plant
Lignin causes the end walls to die so they allow for a long hollow tube to allow water + dissolved minerals to flow easier
How are phloem cells specialised
no nucleus and limited cytoplasm
Sieve tubes
These features allow dissolved sugars to move through of the cell
What is diffusion?
Spreading out of particles of any substance, in solution or a the random movement of a substance from a region of high concentration to a region of low concentration
What is the rate of diffusion affected by?
Difference in concentrations
The temperature
Surface area
What type of substances move by diffusion
Dissolved substances
such as glucose, urea , gases (oxygen and carbon dioxide)
{These substances move in and out of cells by diffusion}
What type of substances move by diffusion
Dissolved substances
such as glucose, urea , gases (oxygen and carbon dioxide)
{These substances move in and out of cells by diffusion}
What is osmosis?
Type of diffusion; It is the movement of water from a dilute to a more concentrated solution through a partially permeable membrane that allows water to pass
What does the term isotonic mean
a solution with the same water concentration as inside a the cel
What does the term hypertonic mean?
The solution that is more concentrated (has more dissolved solute and less water)
What does the term hyoptonic mean?
The solution that is more dilute (has less dissolved solute and has more water)
