Cells and Biomolecules All Revision Flashcards
Covalent Bond
A chemical bond formed when two atoms share one or more pairs of electrons.
Cohesion
The attraction between molecules of the same substance, often observed in water molecules.
Adhesion
The attraction between molecules of different substances.
Polar Bond
A type of covalent bond where electrons are shared unequally, resulting in a molecule with a dipole moment.
Water
A polar molecule composed of two hydrogen atoms and one oxygen atom (H₂O).
Solvent
A substance that dissolves a solute, resulting in a solution.
Buoyancy
The ability of an object to float in a fluid due to the upward force exerted by the fluid.
Hydrogen Bond
A weak bond between two molecules resulting from an electrostatic attraction.
DNA
Deoxyribonucleic acid, a molecule that carries genetic information.
Nucleotide
The basic building block of nucleic acids, consisting of a sugar, a phosphate group, and a nitrogenous base.
RNA
Ribonucleic acid, single strand.
Prokaryote
A unicellular organism that lacks a nucleus and membrane-bound organelles.
Eukaryotes
Organisms whose cells contain a nucleus and other organelles enclosed within membranes.
Cell Theory
The scientific theory that all living organisms are made of cells.
Condensation Reaction
A chemical reaction where two molecules combine to form a larger molecule, with water produced.
Monomer
A small molecule that can bind to other similar molecules to form a polymer.
Hydrolysis Reaction
A chemical reaction where a molecule is split into two parts by adding a water molecule.
Monosaccharides
The simplest form of carbohydrates, consisting of a single sugar molecule.
Polysaccharides
Carbohydrates composed of long chains of monosaccharide units.
Alpha Glucose
A form of glucose with the hydroxyl group on the first carbon below the plane of the ring.
Beta Glucose
A form of glucose with the hydroxyl group on the first carbon above the plane of the ring.
Cellulose
A polysaccharide consisting of beta glucose units, forming plant cell walls.
Glycogen
A polysaccharide serving as energy storage in animals and fungi, composed of alpha glucose units.
Amylose
A polysaccharide made of alpha glucose units, a component of starch.
Amylopectin
A branched polysaccharide made of alpha glucose units, a component of starch.
1-4 Glycosidic Link
A covalent bond joining a carbohydrate molecule to another group, formed between the first and fourth carbon atoms.
1-6 Glycosidic Link
A covalent bond joining a carbohydrate molecule to another group, formed between the first and sixth carbon atoms.
Lipids
Naturally occurring molecules including fats, waxes, sterols, and fat-soluble vitamins.
Hydrophobic
Having a tendency to repel or fail to mix with water.
Hydrophilic
Having a tendency to mix with or be attracted to water.
Amphipathic
A molecule having both hydrophobic and hydrophilic parts.
Triglycerides
A type of fat composed of glycerol and three fatty acids.
Glycerol
A compound forming the backbone of triglycerides.
Saturated Fatty Acid
A fatty acid with no double bonds between carbon atoms, saturated with hydrogen atoms.
Phospholipid
A lipid containing a phosphate group, important in cell membranes.
Monounsaturated Fatty Acid
A fatty acid with one double bond between carbon atoms.
Polyunsaturated Fatty Acid
A fatty acid with more than one double bond between carbon atoms.
Cis and Trans Fatty Acids
Types of unsaturated fatty acids differing in the arrangement of hydrogen atoms around the double bond.
Amino Acid
Building blocks of proteins, containing an amino group, carboxyl group, and R group.
Peptide Bond
A covalent bond linking amino acids in proteins.
Protein
A molecule composed of amino acids, essential for body structure and function.
Diffusion
The movement of particles from higher to lower concentration.
Facilitated Diffusion
Passive transport of molecules across membranes via specific channel proteins.
Osmosis
Movement of water through a selectively permeable membrane from lower to higher solute concentration.
Channel Proteins
Proteins forming channels allowing specific molecules or ions through cell membranes.
Protein Pumps
Proteins using energy to transport molecules against concentration gradients across cell membranes.
Selectively Permeable
Membrane property allowing some substances to pass while blocking others.
Glycoprotein
Protein with attached carbohydrate chains, involved in cell recognition.
Glycolipid
Lipid with attached carbohydrate chains, involved in cell recognition.
Fluid Mosaic Model
Model describing cell membrane structure as a fluid mosaic of various components.
Nucleus
Membrane-bound organelle containing genetic material in eukaryotic cells.
Mitochondria
Organelles producing ATP, providing cellular energy.
Ribosomes
Organelles synthesizing proteins from messenger RNA.
Endoplasmic Reticulum
Membrane network involved in protein and lipid synthesis.
Golgi Apparatus
Organelle modifying, sorting, and packaging proteins and lipids.
Chloroplast
Organelle conducting photosynthesis in plant cells.
Cell Wall
Rigid layer providing support and protection in plant cells.
Cell Membrane
Biological membrane separating cell interior from exterior.
Stem Cells
Undifferentiated cells capable of developing into various cell types.
Unspecialised Cell
Cell not yet specialized into a specific type.
Totipotent
Cells capable of developing into any cell type, including placental cells.
Pluripotent
Cells capable of developing into any cell type except placental cells.
Multipotent
Cells capable of developing into multiple but not all cell types.
Stem Cell Niche
Microenvironment regulating stem cell function.
Hypotonic Solution
Solution with lower solute concentration than another solution.
Hypertonic Solution
Solution with higher solute concentration than another solution.
Isotonic Solution
Solution with same solute concentration as another solution.
