Cell structure and function Flashcards
What are all living things made of
One or more cell
Are cells visible to the naked eye
No
Where does the exchange of materials occur?
Plasma membrane
Prokaryotic cell characteristics:-
- 1-2um
- No membrane bound organelles
- Ribosomes present
- Complex cell wall
*EG. Bacteria
Eukaryotic cell characteristics:-
- 10-100um
- Membrane bound organelles
- Ribosomes
- Cell wall not in animal cells
- Animal
Formula for sa of sphere?
4pir^2
Formula for volume of sphere?
4pir^2/3
Can the organelles access the plasma membrane faster in large cells of smaller cells?
Large cells
Characteristics of Cell wall:-
- Semi-rigid
- Maintains shape and gives support and strength
- Eg. Plant, Fungi, Bacteria
Cell wall structure plant cells?
- Primary cell wall - made of cellulose
- Secondary cell wall - cellulose and ligning (for woody plants) It thickens and causes cells to die which gives the rough wood texture.
What is Chloroplast?
Chloroplast is a green organelle with folded membranes called Grana and undergoes photosynthesis and stores starch.
What is a plasma membrane?
The plasma membrane is semi permeable and protects the cell and controls what substances enter and exit the cell.
What is the nucleus:?
The nucleus is the control center of the cell controlling the activities inside the cell. It has a nucleolus with RNA and nuclear envelope with pores letting substances move around the nucleus and cytoplasm.
What is the mitochondrion?
The mitochondrion is the powerhouse of a cell creating energy for the cell called Adenosine Triphosphate ( ATP) through cellular respiration. It has an inner and outer membrane called the CRISTAE and MATRIX inside the cristae.
What are ribosomes?
Ribosomes are the factories for cells they create proteins in the ROUGH ER or in CYTOSOL (fluid part of cytoplasm) they are made of amino acids formed into polypeptide chains/proteins.
What is the ER
The endoplasmic reticulum is the transport for the cell. the rough ER transports proteins made by by the ribosomes within the cell and the Smooth ER kills harmful products, stores and releases products. It also forms sugar groups for glycoproteins, folding proteins and making polypeptides for ribosomes.
What is the golgi complex
The golgi complex is also transportation in the cell. It packages proteins and other materials into vesicles to be transferred outside of the cell.
what are lysosomes
Lysosomes are the trash bins of the cell they digest waste and kill nonfunctioning organelles and toxic substances.
what are peroxisomes
Peroxisomes kill toxic substances that enter the bloodstream
What are endosomes
Endosomes pass recent waste to lysosomes
What does the cell skeleton do?
The cell skeleton give strength and support, maintain cell shape, movement of organelles, move chromosomes. They are made of Microtubules, Intermediate filaments and microfilaments.
What do the proteins in the plasma membrane do
They change behaviours in response signals, communicate with other cells, serve as identity markers, act as receptors.
What proteins are in the plasma membrane
In the plasma membrane there are glycoproteins, integral proteins, and peripheral proteins. On the surface of the membrane are glycolipids that communicate to other cells and cholesterol in the membrane which let the membrane move.
what are the two types of transport in the plasma membrane
Passive transport and active transport
What is osmosis?
Osmosis is the diffusion of water particles through the semi permeable plasma membrane via passive transport.
What is osmolarity?
Osmolarity is the total solvent concentration in a solution.
What are the three types of osmolarity?
Isotonic solution, hypertonic solution and hypotonic solution
What is an isotonic solution
Isotonic solutions are when there is an equilibrium of solute concentration compared to another solution.
What is a hypertonic solution?
A hypertonic solution has more solute and less water. Because there is more substance on the solution the water exits the solution to a lower concentration of solute.
What is a hypotonic solution
A hypotonic solution has more water and less solute. This is because there is less concentration of solute so the water moves to this solution.
What is facilitated diffusion (passive transport)
Facilitated diffusion is a type of passive transport where particles diffuse across the semi permeable plasma membrane via (channel) proteins in the membrane. This is still passive transport because there is no such energy used.
What is passive transport?
It is the diffusion of particles between the semi permeable plasma membrane without the use of energy
What is active transport?
Active transport is the movement of substances travelling from low concentration to high concentration (against its concentration gradient) with the use of ADP AND PI energy from ATP energy and carrier proteins which act as a lift for the substances.
An example of active transport?
The movement of glucose from the small intestines into the large intestines is an example of active transport.
What is exocytosis?
The transport of substances out of the cell. Exo meaning out
What proteins are involved in exocytosis?
Nucleus- blueprint for proteins which is then translated into protein by rRNA
Ribosomes- makes protein
ER - transports to golgi complex
Golgi complex - packages into vesicles and out of the cell.
What are the ribosomes in the ROUGH ER for?
They are produced there for transportation and to be used in the lysosomes for digestion.
What are vesicles
Vesicles are small packages in the cell which transport substances from the Golgi body to outside the cell.
The vesicle membrane then fuses with the plasma membrane and releases the substances outside of the cell.
