List the functions of water, carbs and lipids
Water - Blood volume, temp, blood pressure. lubrication, transport
Carbs - Energy, Nervous system
Lipids - Absorption of vitamins, cell membranes, Insulation
What is the difference between glycogen and glucose in terms of location and general
structure and function?
Glucose is a monosaccharide while glycogen is a polysaccharide ( many units)
Blood Vs Muscles/Liver
What are the names of the processes by which polysaccharides are formed and
broken down? In which of these is water used, or formed?
Hydrolysis - Water Used
What are the main types of lipid found in the body?
Triglycerides. Triglycerides are lipids you obtain from food sources of fat, such as cooking oils, butter and animal fat. …
Steroids. Steroids are a type of lipid that includes hormones and cholesterol. …
Phospholipids.
What are the products of triglyceride breakdown?
free fatty acids and glycerol. Fatty acids can then be taken up by cells via the fatty acid transporter (FAT).
. State the functions of proteins
Repair, Muscle building, DNA
Describe the basic structure of proteins.
The primary structure of a protein refers to the linear sequence of amino acids in the polypeptide chain. The primary structure is held together by covalent bonds such as peptide bonds, which are made during the process of protein biosynthesis.
What is meant by secondary, tertiary and quaternary protein structure?
Secondary - aminos linked by hydrogen bonds
Teriary - 3D SHAPE The protein molecule will bend and twist in such a way as to achieve maximum stability or lowest energy state. fashioned by many stabilizing forces due to bonding interactions between the side-chain groups of the amino acids.
Quartenart - Formation of protein subunits
. What is denaturation of proteins and what are the causes?
Disruption/destruction of secondary/ tertiary to Primary
Heat
What are conjugated proteins?
A conjugated protein is a protein that functions in interaction with other (non-polypeptide) chemical groups attached by covalent bonding or weak interactions. ie., lipoprotein
Define the term ‘enzyme’.
Enzymes are macromolecular biological catalysts
How do enzymes co-operate?
By folding to allow smaller molecules to fit
. Describe how enzymes work, i.e. ‘induced fit’.
the binding of a substrate or some other molecule to an enzyme causes a change in the shape of the enzyme so as to enhance or inhibit its activity.
What factors can affect enzyme activity? In each case explain the reason why
Temp (more random collisons, pH, Substrate concentration, bonding ETC
Describe the difference between the following co-factors:
Activators (give examples)
Prosthetic groups (give examples)
Co-enzymes (give examples)
activators are molecules that bind to enzymes and increase their activity. They are the opposite of enzyme inhibitors.
Prosthetic groups are cofactors that bind tightly to proteins or enzymes. A
Co Enzymes - molecules that increase the rate of reaction or are required for enzyme function
What are: Reversible inhibitors (give examples) Irreversible inhibitors (give examples)
Non reversible - Chemical change
Reversible - Non-covalent bond
Define: Homeostasis; Negative feedback; Dynamic equilibrium; 'Open system
Negative feedback causes a decrease in function. Often it causes the output of a system to be lessened; so, the feedback tends to stabilize the system.
Dynamic Eq. - balancing when a cell requires energy to maintain
an Open system is one in which materials and energy are transferred between organisms and the exterior environment. In an open system, there is some type of boundary that allows energy or materials to cross over for the purpose of growth and change.
What is the difference between positive feedback and negative feedback? Give an
example of each.
A positive feedback loop causes a self-amplifying cycle where a physiological change leads to even greater change in the same direction. A negative feedback loop is a process in which the body senses a change, and activates mechanisms to reverse that change.
What is the structural arrangement of phospholipid in a cell membrane?
Middle hates water!
What other lipids are present in a cell membrane and what are their functions?
classes of membrane lipids are phospholipids, glycolipids, and cholesterol.
Glyco Their role is to maintain stability of the membrane and to facilitate cellular recognition.
Cholesterol essential to maintain both membrane structural integrity and fluidity
Phospho - form BI layer
What are the functions of membrane proteins?
Interaction, signalling, Transport
. What are the functions and properties of the plasma membrane?
Protection/movement of substances
Give an example of:
a. a cell that does not contain a nucleus,
b. a cell that is multinucleate.
Prokaryotes (meaning ‘before nucleus’) are cells without a definite nucleus.DNA floats in the cytoplasm and they divide through mitosis E.COLI
Multinucleate cells (also called multinucleated or polynuclear cells) are eukaryotic cells that have more than one nucleus per cell, i.e., multiple nuclei share one common cytoplasm. - MUSCLE
What does the term ‘syncytium’ mean?
a single cell or cytoplasmic mass containing several nuclei, formed by fusion of cells or by division of nuclei.
