Review B1 Cell Biology Flashcards
What is osmosis?
The diffusion of water through a partially permeable membrane from an area of high concentrated solution to an area of low concentrated solution down a concentration gradient.
What is diffusion?
Resulting in?
The spreading out of particles of any substance in a solution, or particles in a gas.
Resulting in a net movement of particles from an area of high concentration to an area of lower concentration, down a concentration gradient.
What is isotonic?
Is when the concentration of solutes in the solution outside the cell is the same as the internal concentration
What is hypertonic?
It is when the concentration of solutes in the solution outside the cell is higher than the internal concentration.
What is hypotonic ?
It is when the concentration of solutes in the solution outside the cell is lower than the internal concentration.
What is ‘net movement’
Particles moving in minus particles moving out
What is a partially permeable membrane?
A membrane that only allows certain substances to pass through.
What is cell differentiation?
Usually to what?
It is where a cell changes from cell type to another.
Usually to a more specialised cell type.
What are stem cells?
Like what?
They are cells of the bodywhich can divide and become differentiated.
When organisms grow, stem cells specialise and take specific functions.
What do these have in common?
Skin,blood,muscle,bone, nerves.
They all have different types of cells.
What is the first stage of mitosis?
Spindle formed chromosomes are duplicated and arranged along the equator.
What is the second stage of mitosis?
Chromosomes single strands move to the poles of the cell, the nucleus divides into two.
What happens in the third stage of mitosis?
The cell divides into two to produce two identical daughter cells
What are daughter cells ?
New cells that are genetically identical to the original cell.
Some organisms can be reproduced by mitosis what is that called?
It is called asexual reproduction.
What is the nucleus?
The part of a cell that contains genetic information
What is the diploid?
The full number of chromosomes
What is magnification?
It is the size of image over the size of specimen.
What is a light microscope?
uses visible light and a system of lenses to magnify small sample images.
What are bacteria?
Prokaryotes or eukaryotes?
Prokaryotes
What does the word ‘organelles’ mean?
It means little organs.
What are two big differences between prokaryotic and eukaryotic cells?
Prokaryotes don’t have a nucleus and they have different organelles.
What is a benefit of having the DNA housed in the nucleus?
It protects the DNA
What is photosynthesis?
Water + light reacts to make chemical energy.
What are alleles?
Different forms of a gene.
What does it mean by being dominant?
Allele which controls the characteristic whenever it is present.
What does it mean by being recessive?
An allele who’s characteristics only show up when it is present on both chromosomes.
What does it meant when it says homozygous?
It’s when 2 alleles are the same.
What does it mean when it says heterozygous?
When two alleles are different.
What does it mean when it says genotype?
The two alleles of the genes are present.
Eg. BB, Bb,bb
What does it mean when it says phenotype?
It is the physical appearance of characteristics
Eg. Brown,blue,green.
