Cells Flashcards
What types of cells are eukaryotic?
Animal, plant, fungi, algae, protozoa
What types of cells are prokaryotic?
Bacteria, archaea.
What are the roles of the proteins embedded in the phospholipid bilayer?
They act as receptors to detect chemical messengers and signalling molecules in the fluid surrounding cells (extracellular fluid).
Do prokaryotic cells have nuclear membranes?
No.
Do eukaryotic cells have nuclear membranes?
Yes.
Are there any membrane bound organelles in prokaryotic cells?
No.
Are there any membrane bound organelles in eukaryotic cells?
Yes.
How does the cytoskeleton maintain internal cell order?
Holds organelles in place.
How does the cytoskeleton assist w intracellular transport?
Helps move organelles around the cell.
How does the cytoskeleton assist with movement?
Drives and guides cellular migration.
How does the cytoskeleton assist with the assembly of tissues?
Protein fibres of the cytoskeleton connect with protein fibres in the extracellular space.
Where would you find cilia?
Lungs
Give an example of a flagella.
Sperm
Describe the structure of cilia.
Short, usually multiple together. Move with stiff power stroke and flexible recovery stroke.
What do cilia do?
Help to move mucus.
Describe the structure of flagella?
Longer, usually more than one and has snakelike movement.
What is the nucleus enclosed in?
Nuclear membrane/envelope which, like all biological membranes, is a phospholipid bilayer.
How many different types of cells are we made up of?
Approx. 200
What are nuclioli?
Sites of ribosomal RNA synthesis and ribosome assembly.
Is the nuleus closely associated w the SER or the RER?
RER
Is the Golgi Apparatus a membrane bound organelle?
Yes
Are the SER and RER membrane bound organelles?
Yes
What do ribosomes do?
Synthesise proteins.
What does the RER do?
Modifies proteins.
What is the SER associated with?
Lipid and steroid hormone production and the metabolism of toxins.
What does the Golgi apparatus do?
Packages up protein in preparation for transport out of the cell.
Mitochondria is bound by…?
A phospholipid bilayer.
How many membranes do mitochondria have?
Two- outer and inner.
Describe the inner membrane of the mitochondria.
Has folds (cristae) which extends to the matrix.
Describe the outer membrane of the mitochondria.
Has pores.
The matrix of the mitochondria contains…?
Most of the enzymes required for metabolising foo molecules (e.g. Krebs Cycle).
What shape is the DNA of mitochondria?
Circular.
The mitochondria has it’s own…?
Ribosomes
Mitochondria can…
- synthesise most of their own proteins.
2.self-replicate
Describe lysosomes and peroxisomes (in terms of where they are bound and what they do).
Membrane bound organelles containing enzymes. They separate enzymes from the rest of the cell and store them until needed.
Lysosomes are degrative; what does this mean?
They are responsible for the digestion of biological matter or digestion of engulfed particles.
Give an example of biological matter that lysosomes may digest.
Cells own materials/autophagy.
What do peroxisomal enzymes do?
They degrade long-chain fatty acids and other foreign toxic molecules.
What do the reactions caused by degradation of fatty acids by peroxisomal enzymes release?
Hydrogen peroxide (toxic).
What do peroxisomes do to the hydrogen peroxide?
Break them using catalase enzymes which protects the cell.
What does pluripotent mean?
Can differentiate into all cell types.
What does multipotent mean?
Has limited differentiation ability and can differentiate into many cells types.
How many different types of cell do we have?
200 approx.
What happens to undifferentiated stem cells?
They divide and produce genetically identical daughter cells.
How do daughter cells develop into different cells?
Differences in gene expression and the local cellular environment.
Define apoptosis.
Programmed cell death. It is a normal cellular process.
Define necrosis.
Untimely death of cells, in response to injruy or infection. It is not normal.
What does cell proliferation mean?
A vast increase in the number of cells.
If there is a loss in balance between cell proliferation and apoptosis, what may occur?
Cancer.
What are the four basic elements of macromolecules?
Carbon, Hydrogen, Oxygen and Nitrogen.
Name one of the seven elements required by the body in relatively large amounts.
Sodium, Magnesium, Potassium, Calcium, Phosphorus, Sulfur and Chlorine.
Name one of the ‘trace’ elements which are essential for the body but only required in small amounts.
Iron, Iodine, Zinc.
How does the body get the elements it requires?
Through the diet.
How many electrons can fit in the first energy level?
2
How many electrons can fit in the second energy level?
8
How many electrons can fit in the third energy level?
18
How many electrons can fit in the outermost energy level?
8
Define molecule.
Two or more elements bonded together.
Which element makes up the basis of almost all biomolecules? Why?
Carbon. Due to bonding versatility.
Name some functional groups.
Hydroxyl, phosphate, amino, carboxyl (acid).
Define configuration.
The fixed arrangement of atoms in a molecule.
What is one disadvantage of carbon double bonds when it comes to structure?
Structure is very rigid and can only interconvert by breaking and reforming bonds which requires a lot of energy.
What is the term used to describe groups on the same side as the double bond?
Cis.
What term is used to describe groups on opposite sides of the double bond?
Trans.
What is the other word for symmetrical?
achiral
What is the other word for asymmetrical?
Chiral
Asymmetrical carbon molecules can be either…
L (laevo) or D (dextro).
Define conformation.
The spatial arrangement of groups that can have different positions in space due to the freedom of rotation of single bonds.
Name the five chemical reactions of life.
- Redox
- Making and breaking of C-C bonds.
- Internal rearrangements.
- Group transfers
- Hydrolysis and condensation.
OIL
Oxidation is loss (of electrons/negative charge so a gain of positive charge).
RIG
Reduction is gain (of electrons/ negative charge).
What kind of agent is NAD+?
Oxidising agent.
What type of agent is NADH?
Reducing agent.
Name a process involving the breaking of C-C bonds
Glycolysis.
Name a process involving the making of C-C bonds
Gluconogenesis.
Name a process involving the making of C-C bonds
Gluconeogenesis.
Give an example of an internal rearrangement.
Glycolysis.
Give an example of a group transfer.
Glycolysis.
Define hydrolysis.
Breaking up a larger molecule using water.
Define condensation.
Two smaller molecules combine to form a larger molecule and release water in the process.
Name four macromolecules.
Protein, lipids, nucleic acids and carbohydrates.
What reation forms polypeptide chains?
Condesation.
What reaction forms polypeptide chains?
Condensation.
Name the DNA base pairings.
Adenine-Thymine.
Guanine-Cytosine.
Name the RNA base pairings.
Adenine-Uracil.
Guanine-Cytosine.
What do lipids mainly consist of?
Repeating units of fatty acids.
What do the bonds look like in saturated molecules?
All bonds are single.
What do the bonds look like in a mono-unsaturated molecule?
There is one double bond.
What do the bonds look like in a poly-unsaturated molecule?
There are more than one double bond.
The more unsaturated???
The more double bonds.
What is trglyceride made up of?
Glycerol + 3 fatty acids.
What are phospholipids composed of?
Glycerol + 2 fatty acids + phosphate group.
What are sterols?
Structural lipids found in the cell membrane.
What is the most important sterol in humans?
Cholestrol.
What is an amphipathic molecule?
A molecule which has a hydrophobic part and a hydrophilic part.
What do functional groups do?
Give specific properties to molecules.
Is the cytoskeleton a organelle?
No
