Cells and Tissues Flashcards
The three principles of cell theory
All living things are made up of one or more cells, this means that cells can be unicellular and multicellular.
cells are the most basic unit of structure of living things.
all cells are created by pre-existing cells.
what is the phospholipid bilayer?
a double layer of phospholipids witht the hydrophobic head groups on the outside.
nucleas
largest organelle, surrouned by th enuclear envelope. this is a double membrane that has many gaps/pores.
Contains genetic information in the form of DNA. The DNA is combined wiht proteins known as histones; this forms the complex called the cromatin, which is i coiled and forms the chromosomes.
whats the structure and function of a mitocondria?
Site of aerobic respiration Site of ATP production.
mitocondria is a double mmbrane the inner membrane is folded into cristates,
Structure and fuction of a ribosome
ribosomes are the smallest of the organelles and are the site of protein synthensis.
Ribosomes use the information coded into an mRNA molecule to assemble the correct order of amino acids in the protein.
Rough and smooth endoplasmic reticulum.
a system of membrane bound flatten sacs. Rough endo plasmic reticulum has ribosmomes attached to its outer surface.
protiens will be released from the cell incoorporated into the plasma membrane are made on these attached ribosomes and then folded and transported in the RER to gogil apparatus
Golgi apparatus
is a stack of flattended sacs known as cistone . Each cisterna surrounded by a single membrane and filled with fluid
it modifies protiens that have been transpoted from the rer eg. adding carbohydrates to them.
These modified proteins are then transported by the golgi versicles. That form when the ends of the cisternae are pinched off.
These can form lysosomes. Others called secretory vesicles carry there contents to the plasma membrane where the are released to the outside of the cell.
lysosomes
the cells recycling facility. When proteins and other components get worn out they are moved to lysosomes. Digestive enzymes break these down into constitutes.
eg. amino acids that can be re-used to make new proteins.
Lysosomes are also involed in the digestion of pathogens. Which are taken into the cell by the process of phagocytosis.
Centrioles
structures which are made of tublar protien called tubulin.
Formation of the spindles , as well as the formation of the cillia and the fagella.
chloroplast
enclosed by an envelope and contain membranes called thylakoids arranged in stackes called grana
Site of photosynthensis.
cell wall (plants)
consist of the carbohydrate cellulose
provides strenght and rigidity for protection and support.
cell vacule in plants
fluid filled sacs surrounded by a single membrane.
The fluid is a dilute solution of molecules and ions the vacuole is used to store mineral salts amino acids sugars ansd waste products.
Stem cells
undifferiated non-specilised cells that give rise to one or more types of cell
