cell structure and transport Flashcards
Draw and label a diagram of an animal cell that includes a nucleus, ribosomes, a golgi body, rough and smooth endoplasmic reticulum and mitochondria.
describe the functions of vacuoles
Vacuoles store waste materilas or products that are produced
- Describe the function of the smooth endoplasmic reticulum.
Smooth ER responsible for synthesis of lipids and production and secretion of steroid hormones.
- The rough ER, studded with millions of membrane bound ribosomes, is involved with the production, folding, quality control and despatch of some proteins.
What features of cells (organelles) are always found in both prokaryotes and eukaryotes?
Features that are found in both prokaryotic and eukaryotic cells are ribosomes, nuclieic acid, cytoplasm, type of cell membrane
- Explain the importance of having compartments (membrane bound organelles) in Eukaryotic cells.
This allows organelles within the cells to control what enters and leaves it by using a selectively permeable membrane. this allows reactions to occur at a more efficient rate
outline why prokaryotic cells have limited function
because they do not contain membrane bound organelles meaning its cellular processes arent as efficient as eukaryotic cells
- What are the four classes of biological molecules?
The 4 classes of biological molecules are lipids, nucleic acid, carbohydrates, proteins
- Discuss the structure of carbohydrates in terms of chemical composition and varying size.
Carbohydrates are made up of 1C 2H 1O simple sugar= monosaccharide 2 sugars connected= disaccharide Multiple sugars= polysaccharides They're the body's primary source of energy and the brain's preferred energy source, carbs are broken down in the body by glucose which is a sugar.
Discuss the four key roles of lipids in cell structure/function.
lipids are energy stores, transport of substances in and out of the cells, protection of cells, a structural components of cell membrane
PEST
- Of the 20 amino acids found in human cells, 9 are considered “essential amino acids”. Explain what is meant by this statement.
9 amino acids are essential because they cannot be synthesised by cells in your body. The rest of the amino acid are synthesised (It is the process of combining two or more components to produce an entity.)
- Why are proteins folded? What happens when they’re misfolded?
Proteins are folded to make them more useful and to function correctly . Alzheimers, parkinsons are caused by misfolded proteins larger.
- Describe why it is important for lipids to be long chains.
Its important for lipids to be in long chains as it makes them non polar which means that theyre water resistant not allowing water in.
Draw a diagram of a mitochondria and label the following:
matrix, cristae, outer membrane, inner membranem intermembrane.
also explain how the structure is specialised for mass production of atp
Matrix- a nutrient rish fuild that provides all the resources and reactants needed for the production of ATP
Cristae- rich with enzymes known as atp synthases
Outer membrane-
inner membrane- has inner folds called the cristae
the cristae structure allows for a larger surface area meaning more reactions can take place, these cristae are also rich with enzymes known as ATP synthases
- State 3 independent different forms of evidence for the endosymbiotic theory and explain how they support the theory.
- both have 2 cell membranes
- contain their own DNA and ribosomes
- replicate through binary fission
what is the endosymbiotic theory?
this theory proposes that mitiochondria were once a small bacterial cell that were consumed by a larger prokaryotic cell and rather than breaking down the 2 formed a symbiotic relationship
Discuss the structure of the phospholipid bilayer shown on the left. Include in your discussion the importance of the.
This structure is made up of 2 different lipids, each containing hydrophilic phosphate head and hydrophobic tails. Phospholipids pair up and the hydrophobic tails pair up so their tails are facing eachother both repelled from water
Describe the role of adhesion proteins in the cell membrane.
Used to join cells together to form tissue
- enables interactions and communication from other cells
- allows to maintain shape
Recognition proteins (glycoproteins) are important signaling molecules. Describe the role of these proteins in blood transfusions and why it is so important to only receive blood from those with the same type blood as you.
These act as a flag which allows immune cells to differentiate between host cells and foreign cells. Once the wrong type of blood has been infused the recognition proteins will pick it up and trigger the patients immune system to attack the transfused blood.
Explain the term “concentration gradient”
concentration gradient is the difference in concentration from one area to another. if one side has high concentration and the other side has low then there is a high doncentration gradient.
Outline the difference between passive and active transport.
Passive transport does not require energy and include processes like simple diffusion and facilitated diffusion as well as osmosis
Active transport dose require energy and are processes like endocytosis and exocytosis, which are forms of bulk transport
what sthe difference between carrier proteins and channel proteins?
Channel – narrow passage way, allows ions to pass through, when no gradient exist the channels have the ability to close
Carrier – bind and change shape of molecule ans release to other side, depend on the concentration gradient.
draw diagram of a carrier protein and a channel protein
Define the terms hypertonic, hypotonic and isotonic
Hypertonic- the solution has a high concentration in the (solute) than the cell (tiny cell)
Hypotonic- the solution has a low concentration in the (solute) than the cell (large cell)
Isotonic- solution has the same solute concentration than the cell( unchanged size of the cell)
Describe why it is important for red blood cells to be stored in an isotonic solution.
If a cell is placed in an isotonic solution, there will be no net flow of water into or out of the cell, and the cells volume will remain stable.
what are the 2 types of bulk transport? and what do they do?
endocytosis- transport into the cell
2 different types
phagocytosis– engulfs solids into cell
pinocytosis- engulfing liquids
exocytosis transports out of the cell
when is active transport used?
- when the cell needs to work against the concentration gradient
- for example digestive enzymes
. Outline two bodily processes that depend on exocytosis any why they need to use this method of transport.
- Hormones produced in the cells are released into the blood stream by exocytosis like digestive enzymes.
- Nerve cells also use exocytosis to communicate.
Explain why substances that can undergo simple diffusion will typically enter a cell faster than those which rely on facilitated transport.
Because facilitated diffusion has to go through transmport proteins as well as the the phosphide bilayer and simple diffusion allows particles to only pass through the plasma membrane.
. Assuming a cell is trying to acquire a certain type of nutrient through simple diffusion, describe and explain the effect on the rate of transport if: temp increased, concentration outside the cell increased, the concentration inside the cell, the surface are increases
The temperature is increased: the rate of diffusion will increase because there is increased movement meaning there is more contact between the cells
The concentration outside the cell is increased: then the rate of diffusion will increase as the solute is trying to enter the cell
The concentration inside the cell is increased: then the rate of diffusion is decreased ???
The surface area increases: the rate of diffusion is increased as the object has more access points that the particles could enter the object in.
draw a complete diagram of the cell membrane including proteins, cholestrol and the phospholipid bilayer.
whats the name given to the model of the cell membrane
the fluid mosaic model
what is osmosis
osmosis is specific to the diffusion of water molecules, that is the diffusion of the solvent rather than the solute
what is feild of view? how dp you figure out the total magnification ?
is the maximum area visible when looking through the microscope eyepiece
total magnification= ocular magnification (10) x objective magnification ( can be 40,4,10)
list the features of a eukaryotic cell
- much more complex
- can be single or multicellular
- contains membrane bound organelles ( mitochondria, lysosomes)
- DNA contained in nucleus
- varying numbers of chromosomes
list the features of a prokaryotic cell
- very simple and singleed celled
- doesnt contain membrane bound organelles
- no nucleus
- DNA exists as a single cellular chromosome
what are the similarities of prokaryotic and sukaryotic cells
- same type of cell membrane
- both have genetic material in the form of nucleic acid
- both have cytoplasm
- both have ribosomes to make proteins
draw a eukaryotic cell
draw a prokaryotic cell
what do proteins do? and what are the different lengths of amino acids called?
they contribute to structure and function, an enzyme is a special protein that speeds up biochemical processes.
peptides- short chain of amino acids
polypeptides- multiple peptides
chain of polypeptides- proteins
what makes something a biomacromolecule
a large molecule that is used by living organisms in either structural or functional biochemical processes.
how do enzymes work?
the enzyme will bind the substrate at the active site, the enzyme and substrate will chemically bind together and form the enzyme-substrate complex.
what happens when a protein denatures
it unfolds
factors effecting denaturing? what happens to a protein once its denatures?
temp, ph as different cells have differnt optimum conditions
once a protein has denatured its no longer in the requires conformation and it will no longer be able to bind the substrate loosing its ability to catalyse reactions.
whats an inhibitor
molecules effecting the binding of other molecules, they are either competitive or non-competitive
competitive- will bind at the active site to stop the substrate from binding
non-competitve- will bind somewhere else on the enzyme forceing the active site to change shape so the substrate cannot bind with the active site
whats an inhibitor
molecules effecting the binding of other molecules, they are either competitive or non-competitive
competitive- will bind at the active site to stop the substrate from binding
non-competitve- will bind somewhere else on the enzyme forceing the active site to change shape so the substrate cannot bind with the active site
whats an activator
when activators bind together the enzyme is activated
cofactors- are small inorganic substances often metal ions
coenzymes- are organic substances such as vitamins
whats an anabolic enzyme
anabolic enzymes join molecules to create larger molecules and store energy an example of this is DNA ligase
whats a catabolic enzyme
breaksdown molecules into smaller component parts for example amylase
