Biological Molecules Flashcards
What are the two main types of sugars in carbohydrates?
Monosaccharides and disaccharides
Define a solute
A substance that dissolves in a solvent.
What is the primary structure of a protein?
The linear sequence of amino acids in a polypeptide chain.
Explain the term “hydrophobic”
Substances that repel water and do not mix well with it; they are non-polar.
What is a triglyceride?
A lipid made up of one glycerol and three fatty acids; commonly found in fats and oils.
What is the role of cholesterol in cell membranes?
It helps maintain fluidity and stability of the membrane by preventing fatty acid tails from packing too closely together.
Define denaturation in the context of enzymes
The disruption of the weak bonds maintaining an enzyme’s specific shape, leading to a loss of function.
describe the function of mRNA in protein synthesis
mRNA carries genetic information from DNA to the ribosome for protein synthesis.
Explain the induced fit model of enzyme activity
A model suggesting that when a substrate binds to an enzyme, the enzyme undergoes a slight change in shape to better fit the substrate.
What is the genetic code?
The set of rules by which information encoded in genetic material is translated into proteins, comprising codons that specify amino acids.
Define an atom
An atom is the smallest particle of an element.
What is a molecule?
A molecule is formed when two or more atoms are chemically bonded together.
Distinguish between solute and solvent
A solute is the substance that dissolves in a solvent, while a solvent is the substance that dissolves the solute.
What is a hydrogen bond?
A hydrogen bond is a weak interaction that occurs whenever molecules contain an electro negative atom bonded to a positively charged hydrogen atom.
List of key properties of water
Water is a universal solvent, has lower density when frozen, high specific heat capacity, cohesion and surface tension.
What are monosaccharides?
Monosaccharides are the simplest sugars, with a general formula of CnH2nOn
What is the process of hydrolysis?
Hydrolysis is a catabolic reaction where water is used to break down larger molecules by splitting covalent bonds.
Define condensation reaction
A condensation reaction is an anabolic process where two smaller molecules combine to form a larger molecule, producing water in the process.
What is glycogen?
Glycogen is a stored form of glucose found primarily in the liver and muscles, serving as an energy reserve.
Explain the role of glucagon
Glucagon is a hormone produced by the pancreas that raises blood glucose levels by signaling the liver to break down glycogen into glucose.
define hydrophobic substances
Hydrophobic substances repel water and do not mix or dissolve in it because they are non-polar.
What are triglycerides?
Triglycerides are the most common lipids in the body, made up of one glycerol and three fatty acids.
distinguish between saturated and unsaturated fats
Saturated fats have no double bonds between carbon atoms and are usually solid at room temperature, while unsaturated fats contain one or more double bonds, making them liquid at room temperature.
What are globular proteins?
Globular proteins are compact, spherical proteins that are soluble in water and play various roles, including enzymatic activity and transport.
Describe the primary structure of proteins
The primary structure is the linear sequence of amino acids in a polypeptide chain, determining the protein’s unique characteristics.
What is the role of enzymes in proteins?
Enzymes act as catalysts to speed up biochemical reactions without being consumed in the process.
What is the function of DNA?
DNA contains genetic information that encodes the sequence of amino acids in proteins.
What is the function of RNA?
RNA acts as an intermediary that carries instructions from DNA to ribosomes for protein synthesis.
Explain the process of transcription
Transcription occurs in the nucleus where DNA is transcribed into messenger RNA (mRNA), which carries genetic information to the ribosome.
What is the genetic code?
The genetic code consists of codons, sequences of three nucleotides that correspond to specific amino acids, directing protein synthesis.
What is the function of LDL cholesterol?
LDL (Low-density lipoprotein) carries cholesterol from the liver to the cells, but excessive amounts can lead to fatty deposits in artery walls, increasing cardiovascular disease risk.
Describe HDL cholesterol
HDL (High-density lipoprotein) helps remove excess cholesterol from the bloodstream, transporting it back to the liver for excretion, thus reducing cardiovascular disease risk.
What lifestyle changes can help manage cholesterol levels?
Healthy diet, regular exercise, quitting smoking, and medications like statins can help manage cholesterol levels.
What is the function of the cell membrane?
The cell membrane regulates what enters and exits the cell, providing protection and support while maintaining homeostasis.
What is the role of carbohydrates in the body?
Carbohydrates are a primary source of energy for the body, providing glucose for cellular respiration and energy production.
What are essential fatty acids?
Essential fatty acids are fats that the body cannot produce on its own, such as omega-3 and omega-6, and must be obtained from the diet.
What are the main functions of proteins?
Proteins serve structural roles, act as enzymes, transport molecules, provide immunity, and facilitate signaling within and between cells.
What is the role of insulin?
Insulin is a hormone produced by the pancreas that lowers blood glucose levels by facilitating the uptake of glucose into cells.
What are hormones?
Hormones are chemical messengers produced by glands in the endocrine system that regulate various physiological processes in the body.
What is ATP, and why is it important?
ATP (adenosine triphosphate) is the primary energy currency of the cell, providing energy for various cellular processes.
Define metabolism
Metabolism encompasses all biochemical reactions within a cell, including catabolic (breaking down) and anabolic (building up) processes.
define catabolism
Catabolism is the metabolic process that breaks down molecules into smaller units, releasing energy.
What is anabolism?
Anabolism is the metabolic process that builds up larger molecules from smaller ones, requiring energy.
Define enzyme
An enzyme is a biological catalyst that accelerates chemical reactions in the body without being consumed in the process.
What is a substrate?
A substrate is the substance on which an enzyme acts during a biochemical reaction.
Explain the difference between saturated and unsaturated fats
Saturated fats have no double bonds between carbon atoms and are solid at room temperature, while unsaturated fats have one or more double bonds and are liquid at room temperature.
What do nucleic acids play in the body?
Nucleic acids, such as DNA and RNA, store and transmit genetic information, guiding the synthesis of proteins necessary for cellular functions.
What is the structure of a triglyceride, and why is it significant?
A triglyceride consists of one glycerol and three fatty acids. It is significant as it is the main form of fat storage in the body, providing energy reserves.
What are the consequences of high levels of lipids in the blood?
High levels of lipids can lead to atherosclerosis, increasing the risk of coronary heart disease, heart attack, and stroke due to plaque buildup in arteries.
What is the role of the cell membrane?
The cell membrane is a semi-permeable barrier that controls the movement of substances into and out of the cell, maintaining homeostasis.
What is gene expression?
Gene expression is the process by which the information in a gene is used to produce a functional product, such as a protein. It involves two main steps: transcription (DNA to mRNA) and translation (mRNA to protein).
Explain transcription
Transcription is the process by which a segment of DNA is copied into messenger RNA (mRNA) by the enzyme RNA polymerase, which then carries the genetic instructions from the DNA to the ribosome for protein synthesis.
What is translation in gene expression?
Translation is the process where the mRNA sequence is decoded by a ribosome to produce a specific protein. Transfer RNA (tRNA) helps match amino acids to the corresponding codons on the mRNA.
what is the role of mRNA in gene expression?
Messenger RNA (mRNA) carries the genetic instructions from DNA to the ribosomes, where proteins are synthesized. It acts as a template for translation.
