Biochem, cell biology & homeostasis Flashcards
What is this the definition of?
- smallest unit of matter
atom
What is this the definition of?
- group of organs that work together to perform one or more functions
organ system
What is this the definition of?
- What organs are made up of
tissue
What is this the definition of?
- When zooming into the tissue types, they are made up of different … types
cell
What is this the definition of?
- When you break open a cell, you have even smaller parts within that, that are almost like organs for the cell which are called …
organelles
What is this the definition of?
- When you break open the organelles into much smaller parts, for example, when you break open the nucleus you have the DNA
macromolecules and molecules
What are the 4 major elements that make life possible? (organic elements)
- oxygen
- carbon
- hydrogen
- nitrogen
What is the name given to the number of protons in an atom?
atomic number
There is usually the same amount of … as … in an atom?
protons and electrons
What is being described?
- forms of the same atom that differ in their number of neutrons
- are atoms of an element with normal number of protons and electrons, but different numbers of neutrons
- have the same atomic number but different mass numbers
isotopes
What is the name given for the number of protons+neutrons in an atom?
mass number
How do you work out the number of neutrons in an atom?
mass number - atomic number
What is being described?
- the average mass numbers of different isotopes
- different to mass number
relative atomic mass number
Fill in the blanks
… hold molecules together (intramolecular forces) and create temporary connections (intermolecular forces) that are essential to life
chemical bonds
- … are the forces that hold atoms together within a molecule. (stronger than the other)
- …are forces that exist between molecules.
- intramolecular forces
2. intermolecular forces
… is a charged atom or molecule. It is charged because the number of electrons do not equal the number of protons in the atom or molecule.
ion
A positively charged ion is called a … ?
cation
A negatively charged ion is called an … ?
anion
What is being described?
- An … is a medium containing ions that is electrically conducting through the movement of ions, but not conducting electrons.
electrolyte
What are the 3 types of intramolecular forces?
- ionic bond
- covalent bond
- metallic bond
What are the 3 types of intermolecular forces?
- dipole-dipole interactions
- hydrogen bonding
- van der Waal forces
What is this the description of?
- this bond is formed between atoms that have similar electronegativities
- similar affinity for electrons means neither has a tendency to donate them
- they share electrons in order to achieve octet configuration and become more stable
- polar and non polar
covalent bond
What type of covalent bond is being described?
- formed between same atoms or atoms with very similar electronegativities
non-polar
What type of covalent bond is being described?
- formed when atoms of slightly different electronegativities share electrons
polar
What is this the description of?
- type of covalent bonding specifically occurs between atoms of metals
- electrons are free to move through the lattice
- this bond is formed via the attraction of the mobile electrons and the fixed positively charged metal ions
- are present in samples of pure elemental metals, such as gold
metallic bonding
What is this the description of?
- these forces occur when the partially positively charged part of a molecule
- interacts with the partially negative charged part of the neighbouring molecule
- strongest intermolecular force of attraction
dipole-dipole interactions
What is this the description of?
- special kind of dipole-dipole interaction, which are typically stronger than other dipole-dipole interactions
- occurs specifically between a hydrogen atom bonded to either an oxygen, nitrogen or fluorine atom
- plays an important role in holding nucleotide bases together in DNA and RNA
hydrogen bonding
What is this the description of?
- these are the weakest of the intermolecular forces and exist between all types of molecules
- the more electrons a molecule has, the stronger these forces are
van der Waal or London dispersion forces
What is defined as the body’s ‘energy currency’ ?
ATP
All of the chemical reactions that happen in a cell are known as …
cell metabolism
All of the chemical reactions that happen in the body is known as …
metabolism
What are the 4 types of chemical reactions?
- Synthesis reactions
- Decomposition reactions
- Exchange reactions
- Reversible reactions
What type of chemical reaction is being described?
- Reactants A and B combine chemically to form a more complex molecule AB
- AB then stores energy in its bonds
synthesis reactions
What type of chemical reaction is being described?
- The molecule AB is chemically broken down to smaller molecules, A and B
- In doing so, every is released
decomposition reactions
What type of chemical reaction is being described?
- These reactions involve both synthesis and decomposition reactions
- The reactants exchange parts to yield new chemical compounds
exchange reactions
What type of chemical reaction is being described?
- In theory, any chemical reaction can proceed in either direction under the right conditions
- Reactants may synthesise into a product that is later decomposed
- Reversibility is also a quality of exchange reactions
- This is indicated by 2 x half arrows pointing in opposite directions
reversible reactions
What is the description of?
- a series of connected chemical reactions that feed one another
metabolic pathway
What are the 2 types of metabolic pathways?
anabolic and catabolic
What type of metabolic pathway is being described?
- build complex molecules from simpler ones
- need an input of energy
anabolic
What type of metabolic pathway is being described?
- involve the breakdown of complex molecules into simpler ones
- release energy
catabolic
Cellular respiration is an example of …
catabolic pathway
What is the name of the process whereby energy is stored and used in the body?
ATP-ADP cycle
… is something that speeds up a chemical reaction
enzyme
A substance that speeds up a chemical reaction, without being a reactant is called a …
catalyst
Part of the enzyme where the substrate binds is called the … (where the catalytic action happens)
active site
What is being described?
- enzyme activity may be turned up or down
- by activator and inhibitor molecules that bing specifically to the enzyme
regulatory molecules
What is being described?
- many enzymes are only active when bound to non-protein helper molecules known as …
cofactors
What is being described?
- storing enzymes in specific compartments can keep them from doing damage or provide the right conditions for activity
compartmentalisation
What is being described?
- key metabolic enzymes are often inhibited by the end product of the pathway they control
feedback inhibition
Molecules that increase the activity of an enzyme are called …
activators
Molecules that decrease the activity of an enzyme are called …
inhibitors
An inhibitor may bind to an enzyme active site and block binding of the substrate, this is called …
competitive inhibition
An inhibitor does not block the substrate from binding to the active site, this is called …
non-competitive inhibition
What is being described?
- a non-protein chemical which is required for proteins biological activity
cofactor
What is being described?
- are a subset of cofactors that are organic molecules
coenzymes
… is a coenzyme for several enzymes that take part in building protein collagen (part of connective tissue)
vitamin c
The enzyme that builds DNA molecules: DNA polymerase, requires … to function
magnesium ions
What is this the definition of?
A group of atoms bonded together, representing the smallest fundamental unit of a chemical compound that can take part in a chemical reaction
molecule
What are DNA and RNA known as collectively?
nucleic acids
What are the 4 major classes of macromolecules?
- proteins
- lipids
- carbohydrates
- nucleic acids
What are the 4 major elements that make life possible?
- oxygen
- carbon
- hydrogen
- nitrogen
What is being described?
- bodys main source of energy
- 50% total energy intake should come from this
- composed of carbon, hydrogen, oxygen
- quickly digested and absorbed by body
carbohydrates
What is being described?
- a carbohydrate (e.g. starch, cellulose, or glycogen) whose molecules consist of a number of sugar molecules bonded together.
polysaccharide
What is being described? - any of the class of sugars (e.g. glucose) that cannot be hydrolysed to give a simpler sugar.
monosaccharide
What is being described? - any of a class of sugars whose molecules contain two monosaccharide residues.
disaccharide
What are the 2 hormones involved in regulating blood sugar levels?
insulin and glucagon
What is being described?
- richest source of dietary energy, so can readily contribute to weight gain
- provides a concentrated source of energy
- should account for 25-35% of your total energy intake
- composed of carbon, hydrogen, oxygen
- absorbed more slowly than carbohydrates
lipids: fats and oils
What are the 2 types of fatty acids?
saturated and unsaturated
What is being described?
- carry the maximum number of hydrogen bonds possible (saturated with hydrogens)
- usually solid at room temperature
- saturated fat is composed of triglycerides in which most fatty acids are saturated
- strongly linked to high cholesterol and increased risk of heart disease
saturated fatty acids
What is being described?
- lack hydrogen atoms and have at least 1 double bond between the carbon atoms
- include monounsaturated and polyunsaturated fatty acids
- are liquid at room temperature
- unsaturated fat is composed of triglycerides in which most fatty acids are unsaturated
- may play a role in reducing the risk of heart disease
unsaturated fatty acids
What are the 2 types of unsaturated fatty acids?
- monounsaturated
- polyunsaturated
What type of unsaturated fatty acid is being described?
- lacks 2 hydrogen atoms and has 1 double bond between carbons
- composed of triglycerides in which most fatty acids
- found in plant-based liquid oils
monounsaturated
What type of unsaturated fatty acid is being described?
- lacks 4 or more hydrogen atoms and has 2 or more double bond between carbons
- composed of triglycerides in which most fatty acids are polyunsaturated
- found in vegetable and fish oils, walnuts, sunflower seeds, soybean
polyunsaturated
What are the 2 essential fatty acids that the body cannot make and must be supplied in the diet?
- alpha linolenic acid (omega 3)
- linolenic acid (omega 6)
What is being described?
- A two-layered arrangement of phosphate and lipid molecules that form a cell membrane, the hydrophobic lipid ends facing inward and the hydrophilic phosphate ends facing outward.
phospholipid bilayer
What is the phospholipid bilayer made of?
The phospholipid bilayer consists of two layers of phospholipids,
- a hydrophobic, or water-hating, interior
- a hydrophilic, or water-loving, exterior
What are the functions of lipids?
- energy reserve and storage
- heat insulation
- buoyancy
- protection against shock
- structural components of of cell membranes
- biological carriers
- precursors for many hormones and signalling molecules
- sensory appeal of foods and stimulate appetite
What is being described?
- essential for growth and repair and maintenance of good health
- forms main structural components of cells and maintains tissues and muscles
- is the 2nd most abundant compound in the body, after water
- composed of carbon, hydrogen, oxygen and nitrogen
- primary amino acid chains: more complex structure than carbs and lipids
proteins
What are known as the building blocks of proteins?
amino acids
What are the 3 groups of amino acids?
- essential
- conditionally essential
- non-essential
What group of amino acids is being described?
- the body cannot synthesise these in sufficient amounts to meet physiological needs
essential amino acids
What group of amino acids is being described?
- the body can synthesise these
non-essential amino acids
What group of amino acids is being described?
- normally non-essential, but must be supplied by the diet when its needed exceeds the body’s ability to make it
conditionally essential amino acids
What group of amino acids are the following?
- histidine
- isoleucine
- leucine
- methionine
- phenylalanine
- threonine
- tryptophan
- valine
- lysine
essential amino acids
What group of amino acids are the following?
- arginine
- asparagine
- glutamine
- glycine
- proline
- serine
- tyrosine
conditionally essential amino acids
What group of amino acids are the following?
- alanine
- aspartate
- cysteine
- glutamate
- selenocysteine
non-essential amino acids
What are the 4 levels of protein structure?
- primary protein
- secondary protein
- tertiary protein
- quaternary protein
What level of protein structure is being described?
- sequence of a chain of amino acids
primary protein structure
What level of protein structure is being described?
- hydrogen bonding of the peptide backbone causes the amino acids to fold into a repeating pattern
secondary protein structure
What level of protein structure is being described?
- 3D folding pattern of a protein due to side chain interactions
tertiary protein structure
What level of protein structure is being described?
- protein consisting of more than one amino acid chain
quaternary protein structure
What are the functions of proteins?
- growth and maintenance
- enzymes (facilitate chemical reactions)
- hormones (regulate body processes)
- fluid balance
- acid base balance
- transportation of substances
- antibodies
- energy and glucose
What is being described?
- 2/3 of the body consists of organic molecules
- small molecules: only a few atoms and bonds
- usually dissolve in water
- major kinds of inorganic molecules inside cells: water, electrolytes and gases
inorganic molecules
What type of inorganic molecule is being described?
- signalling molecule eg. relaxes smooth muscle, vasodilator
nitric oxide
Name 4 types of electrolytes?
- calcium
- sodium
- potassium
- iron
What is the general function of electrolytes?
- bone and teeth formation
- help maintain salt/water balance
- acid/base balance
What type of electrolyte is being described?
- 99% in bones as reservoir
- role in blood clotting, hormone secretion, muscle contractions
calcium
What type of electrolyte is being described?
- main cation in extracellular fluid
- role in acid/base balance, nerve transmission, muscle contractions
sodium
What type of electrolyte is being described?
- main cation in intracellular fluid
- role in neurotransmission, muscle contraction, steady heartbeat
potassium
What type of electrolyte is being described?
- most of body’s … is in form of haemoglobin and myoglobin for oxygen transport and storage
- another role is as a cofactor in enzymes
iron
What are 6 functions of water?
- universal solvent - chemicals need to be dissolved in a solvent for chemical reactions
- chemical reactant - water molecules are directly used in some important chemical reactions
- ability to stabilise temperature
- acts as a lubricant
- cushioning - water protects organs
- transport medium - moves things around the body
What percentage of the human body is made up of water?
60-65%
Most organisms, including humans, need to maintain pH within a fairly narrow range in order to survive. For instance, human blood needs to keep its pH right around …
7.4
What illness is being described?
- occurs when blood pH falls below 7.35, indicating an increase in H+ ion concentration
acidosis
What illness is being described?
- occurs when blood pH rises above 7.45, indicating a reduction in H+ ion concentration
alkalosis
What is being described?
- solutions that can resist changes in pH
- are key to maintaining stable H+ ion concentrations
- will absorb excess H+ ions when there are too many, bringing pH back up
- will donate some of its own H+ ions when there are too few to reduce the pH
buffers
What is the name of the buffer system, important in maintaining pH in the oral cavity:
- if too many H+ ions build up, the equation will be pushed to the right, bicarbonate ions will absorb the H+ ions to form carbonic acid
- similarly, if H+ ions concentration drops too low, the equation will be pulled to the left
- carbonic acid will turn into bicarbonate, donating H+ ions to the solution
- without this buffer system, the body’s pH would fluctuate enough to put survival in jeopardy
carbonic acid - bicarbonate buffer system
