Molecular and Cellular Biology Flashcards
What is the basic structure of a prokaryote?
microorganisms that belong to the domain bacteria and archea which are single celled and it means before nucleus as it does not have a nucleus. It does not contain a membrane bound organelle and it is a small micro-organism that has size between 0.2 - 2 micrometers.
Structure -
Capsule: usually made up of polysaccharides, that helps the cell to stick to other surfaces, prevent it from drying out and protects against the hosts immune system.
Cell wall: Located underneath the capsule to maintain the cells shape, protects the cell and to maintain the cells osmotic pressure, contains peptidoglycan which is a polymer of linked sugars and polypeptide (archeal cell walls don’t contain peptidoglycan but pseudo-peptidoglycan)
Plasma membrane: Underneath the cell wall lies the plasma membrane which is made up of phospholipids that is composed of a hydrophilic glycerol thats attached to a phosphate head and two hydrophobic fatty acids forming a phospholipid bilayer.
Appendages: Thin filament called fimbria helps stick to surfaces, longer appendages called pili have different roles like sex pili holds two bacterial cells together and allow DNA transfers between them in a process called conjugation. Another class of bacterial pili is the IV pili that helps bacterium move around the environment. The flagella is also used for movement.
Chromosome and plasmid: Most prokaryotes have a single chromosome , having a single compy of their genetic material. prokaryotes genome are generally smaller, chromosome of a prokaryote is formed in parts of cytoplasm called nucleoid.
What is the basic structure of Eukaryotes?
What is the level of organisation in living organism?
-cells: basic unit of life and the smallest unit capable of reproduction. Some cells are found independent of solid tissues and have their own function like a red blood cell.
-tissues: a group of similar cells that carry out specific functions together. There are 4 basic types of tissues -
-Muscle tissue - made up of cells that can contract for movement
-Epithelial tissues - make up the layer of organs
-Nervous tissue - made up of specialised cells that transmit information through electro/chemical impulses such as tissues of nerves, spinal cord and the brain.
- connective tissues - bone tissues made up of fibrous cells and give shape and structure to organs
-organs: structure made up of different tissues that perform specific bodily function, most organs contain tissues like parenchyma (used to perform organ function), stroma (connective tissue specific to organ) ad epithelial.
-Organ system: A collection of organs that work together to perform similar functions.
Matter: anything that takes physical space
Element: substances that can be broke down into other structures by ordinary chemical reaction
Atom: charged particles made up of smallest unit of matter that retain property of element
Compound: atoms 2 or more element held together by chemical bonds
Name different types of chemical bonds and explain them
Covalent bond: when two atoms share an electron such as hydrogen atoms
Ionic bonds: positive and negatively charged ions join together by ionic bond to form a molecule
Hydrogen bond: weak but large in numbers between complementary base pairs of DNA molecules. Shape and chemical structures of bases allow H bond to form efficiently only between AT and CG
Vanderwaals bond: result from random dipole formation between adjacent atoms
Name the the type of compound
non-organic compound: non living and do not contain carbon element
organic compound: living matter and contains carbon
What are the 4 categories of organic molecules and what are their monomers and polymer
Monomer polymer
Carbohydrates - monosaccharide - polysaccharide
protein. - amino acid - polypeptide
lipid - fatty acids, - lipid
glycerol
Nucleic acid. -nucleotide. -nucleic acid
What is a monomer?
smaller units that can be joined together to make a polymer
What is a Polymer?
Formed from monomers through polymerisation. The breakdown of macromolecules into molecules requires water called hydrolysis to break the chemical bonds
-polysaccharide
-polypeptide
-phospholipid
-nucleic acid
What are metabolites?
primary metabolite - substances produced by organism as part of normal growth like lactic acid
secondary metabolite - produced by plant and microorganism and can be used as medicine
Carbohydrates
The biological significance of carbohydrates is that it is the major source of energy in living organisms, that also play an important role in biosynthetic reaction, involved in structural formation of cells and tissues.
general classification of carbohydrates:
monosaccharide - glucose, fructose and galactose
disaccharide - sucrose, lactose
oligosaccharide - malto-triose
polysaccharide - starch, cellulose and dextran
Lipids
Proteins
Nucleic acid
Water
Cell structure
