Biomolecules and Cell types Flashcards
What are the 2 types of cells?
Prokaryotes and Eukaryotes
Detailed table comparing Prokaryotes and Eukaryotes?
What are bacterial infecting viruses called
Bacteriophages
Describe the process of a bacteriophage infecting bacteria?
Bacteriophages attach to the cell wall of a host cell with tail fibers.
Inject viral nuclear material into the host cell.
Bacteriophage nucleic acids reproduce inside the host cells to produce more phages.
Host cells lyse or break apart and phage particles are released which can infect new host cells.
Sometimes phage DNA may be incorporated into the host DNA and the host may continue to multiply in this state.
What are the implications of this bacteriophage infecting cycle?
Viruses cause of many diseases.
Can disrupt bacteria-based fermentation processes disrupting biochemical engineering processeson an industrial plant level.
But also can be beneficial using genetic engineering and gene therapy – e.g. replace viral genetic material with desired genes to be inserted in the patient. The viral capsid protects the inserted gene in the human host until it reaches the targeted cell type
Give the cycle for replication of virulent bacteriopage?
Give some facts about prokaryotes
- Sizes : 0.5 to 3 micrometres
- Many shapes
- Multiply rapidly doubling times in half to a few hours
- Use “barebone” to rich nutrients: CO2 to carbohydrates
What are the 2 distinctions for eubacteria?
Positive gram cell and negative gram cell. These differences reflect differences in cell envelope structure
What are the main differences between a gram positive and negative cell?
A gram positive cell has no outer membrane, its peptidoglycan layer is thicker, and chemicalcomposition of its cell wall differs from outer membrane of gram negative cell.There are other types of bacterial cells e.g not gram positive or negative, that do not have a cell wall
Give the structure of a gram-negative cell.
Give the structure of a gram-positive cell.
What are the principal features of a prokaryote?
Give some key facts about eucaryotes and give the structure.
- Animal cells, plant cells, Fungi (yeasts and molds), algae, protozoa
- 5-10 times larger than procaryotes in diameter e.g. yeast ~5 microns, animal cells ~10 microns, plants ~20 microns
Give the features in eucaryotes
Give some examples of microscopic eucaryotes
Briefly describe the steps in cell division
Cell division consists of Mitosis, where the nucleus divides, cytokinesis where the cell splits into separate daughter cells and the interphase phase where a cell builds up towards the next nuclear division
What’s meiosis?
Special kind of cell division. Each of these two cells is called a gamete and has 23 chromosomes (haploid) as compared to a zygote which has 46 chromosomes.
What are the building blocks of proteins?
Amino acids
What’s the structure of an amino acid?
Amino acids have acidic (carboxyl) groups: -COOH and basic (amino) –NH2 groups
What are the most abundant organic molecules in living cells?
Proteins are the most abundant organic molecules in living cells (40-70% of dry weight)
What are amino acid’s names based on?
They are named based on the R-side group. (occur in two isomeric forms).
How can the charge on the carboxyl and amino groups on an amino acid can be varied?
Changing PH
What’s the pH at which an amino acid has no net charge called?
Isoelectric point. At this point, the amino acid does not migrate under the influence of an electric field
How many amino acids are found in proteins?
20
What defines amino acid’s primary, secondary, tertiary and quarternary structure?
Amino acids determine the protein’s primary structure.
Secondary and tertiary structures are determined by weak interactions among the various side groups.
Quarternary structures arise by combining more than one polypeptide chain.
What are the 5 main categories of proteins and give an example for each.
- Structural proteins: glycoproteins, collagen, keratin
- Catalytic proteins: enzymes
- Transport proteins: haemoglobin (oxygen), serum albumin (fatty acids)
- Regulatory proteins: hormones (insulin, growth hormone) communication – (affect cells elsewhere). Only a small amount of hormone is required to alter cell metabolism. It is essentially a chemical messenger that transports a signal from one cell to another}
- Protective proteins: antibodies, thrombin (ex. prevent pathogens (bacteria, viruses etc)from damaging cells by binding)to them)
What is a substance that bonds to a protein called?
Ligand
What is the dalton and what’s it’s equivalent weight?
The mass of proteins and other organic molecules is sometimes given in Daltons.
1 Dalton = mass of 1 hydrogen atom
So 150 kilodaltons = 150 (1.00797) = 151,195.5 grams/mole protein]
Whats the minimum amount of amino acids a protein has?
50
Below this amount would make the chain a poly-peptide
Give the mechanism for the condensation reaction of amino acids to form peptide
What is the primary structure of a protein?
This is the protein’s linear sequence of amino acids. Each protein has its own sequence.
What is the secondary structure of a protein?
Formed by the way a polypeptide chain is extended. Induced by hydrogen bonding. Two main groups (helixes and sheets)
Draw the alpha-helix and beta-sheet structures of a protein
What is the tertiary structure of a protein?
Results from interactions between R groups via covalent, hydrogen, and disulfide bonds (eg. ribonuclease). The tertiary structure profoundly affects the function
What is the quarternary structure of a protein?
Only proteins with more than one polypeptide chain have quarternary structure, (e.g. haemoglobin has four protein subunits). Bonds between chains can be disulfide or other weak interactions
What are antibodies/immunoglobins?
Proteins that bind to specific molecules or portions of large molecules with high specificity. The foreign macromolecule is called the antigen. The combination of the antibody to the antigen is called the immune response. Antibodies have emerged as an important area of activity in Biotechnology. (also industrially, diagnostic kite e.g. [presence means antigen may be present], protein separations, drug delivery)
