T Level Health: Cells, Biological Molecules, and Cardiovascular Systems

Comprehensive vocabulary flashcards reviewing cell biology, cellular organelles, biological molecules, enzymes, membrane transport, and cardiovascular anatomy and physiology based on T Level Health lecture materials.

Cell

The basic unit of life; all living organisms are made of one or more cells.

Cell Theory

The biological principle stating that all life is made of cells, cells are the basic unit, and cells arise from pre-existing cells.

Stem Cells

Undifferentiated cells that can divide and develop into specialised cell types.

Eukaryotic Cell

A cell containing a distinct nucleus and membrane-bound organelles.

Prokaryotic Cell

A cell with no distinct nucleus or membrane-bound organelles, in which DNA is located in a nucleoid.

Nucleoid

The region of a prokaryotic cell containing its main chromosome DNA.

Plasmids

Small circular DNA molecules, common in bacteria, that replicate independently.

Cristae

Folds of the inner mitochondrial membrane that increase surface area for aerobic respiration and ATP production.

Mitochondrial Matrix

The inner compartment of a mitochondrion containing enzymes, mitochondrial DNA, and ribosomes.

Rough Endoplasmic Reticulum (RER)

An organelle with ribosomes attached that makes, processes, and transports proteins.

Smooth Endoplasmic Reticulum (SER)

An organelle without ribosomes that mainly synthesises and transports lipids.

Golgi Cisterna

A flattened, membrane-bound sac that makes up the Golgi apparatus.

Cis Face of the Golgi

The receiving side of the Golgi apparatus where transport vesicles from the endoplasmic reticulum fuse and deliver cargo.

Trans Face of the Golgi

The shipping side of the Golgi apparatus that sorts and packages modified proteins and lipids into vesicles.

Protein Secretion Pathway

The transport pathway represented by: $\text{RER} \rightarrow \text{transport vesicle} \rightarrow \text{Golgi} \rightarrow \text{secretory vesicle} \rightarrow \text{cell membrane}$.

Lysosomes

Organelles that digest unwanted material and worn or damaged cell components.

Centrioles

Organelles that organise microtubules and help form the spindle during cell division.

Lamins

Proteins supporting the nuclear envelope and maintaining nuclear shape.

Microfilaments

Cytoskeletal fibres made mainly of actin proteins that maintain cell shape and enable cell movement.

Microtubules

Hollow tubes composed of tubulin proteins that act as tracks for transport, form the mitotic spindle during cell division, and maintain cell shape.

Intermediate Filaments

Strong protein fibres that provide structural support, cell strength, and mechanical stability.

Fluid Mosaic Model

A model of membrane structure where 'fluid' indicates phospholipids and some proteins can move, and 'mosaic' describes proteins scattered throughout the phospholipid bilayer.

Transcription

The synthesis of mRNA from a DNA template, occurring in the nucleus in eukaryotic cells.

Translation

The assembly of amino acids into a polypeptide chain at a ribosome using genetic instructions carried by mRNA.

Amino Acid

The monomer unit of proteins, consisting of an amino group, a carboxyl group, a hydrogen atom, and a variable R group.

Peptide Bond

The covalent bond that joins amino acids together via a condensation reaction.

Primary Protein Structure

The specific sequence of amino acids in a polypeptide chain joined by peptide bonds.

Tertiary Protein Structure

The overall 3D shape of a single polypeptide chain.

Quaternary Protein Structure

A protein structure composed of two or more polypeptide subunits joined together, such as haemoglobin.

Triglyceride

A lipid molecule composed of one glycerol molecule joined to three fatty acids by ester bonds.

Enzyme

A protein that acts as a biological catalyst, speeding up a biochemical reaction without being consumed.

Denaturation

A structural change in the shape of a protein's active site caused by high temperatures or extreme pH, preventing it from functioning.

Facilitated Diffusion

Passive net movement of substances down a concentration gradient using transport proteins without requiring ATP.

Active Transport

The movement of substances against a concentration gradient, from low to high concentration, requiring ATP.

Osmosis

The passive net movement of water molecules across a partially permeable membrane from a higher water potential to a lower water potential.

Deamination

The metabolic removal of an amino group from an amino acid occurring in the liver, producing toxic ammonia which is converted to urea.

Nephron

The functional unit of the kidney responsible for filtration, selective reabsorption, and secretion to remove urea, excess water, and ions.

Blood Plasma

The liquid component of blood that transports dissolved nutrients, wastes, antibodies, and hormones.

Platelets

Cell fragments in the blood involved in haemostasis and clotting by assisting in the formation of a fibrin mesh.

Neutrophils

Phagocytic white blood cells that constitute approximately $50\text{--}70\%$ of all leukocytes and rapidly engulf and destroy pathogens.

B Lymphocytes

White blood cells that produce specific antibodies to recognise antigens and target pathogens.

Microcirculation

The passage of blood through the smallest vessels in the sequence: $\text{arterioles} \rightarrow \text{capillaries} \rightarrow \text{venules}$.

Pulmonary Circulation

The pathway of blood flow between the heart and lungs: $\text{right ventricle} \rightarrow \text{pulmonary artery} \rightarrow \text{lungs} \rightarrow \text{pulmonary veins} \rightarrow \text{left atrium}$.

Systemic Circulation

The pathway of blood flow between the heart and body tissues: $\text{left ventricle} \rightarrow \text{aorta} \rightarrow \text{body} \rightarrow \text{venae cavae} \rightarrow \text{right atrium}$.

Coronary Circulation

The dedicated circulation supplying oxygenated blood to the myocardium via coronary arteries and draining into the right atrium via the coronary sinus.

Sinoatrial Node (SAN)

The heart's natural pacemaker that initiates electrical impulses triggering each heartbeat.

Atrioventricular Node (AVN)

A node in the cardiac conduction system that briefly delays the electrical impulse so the atria can empty before the ventricles contract.

Purkinje Fibres

Conductive fibres that rapidly spread electrical impulses through the ventricles to coordinate ventricular contraction.

Cardiac Cycle

The complete sequence of events during one heartbeat, encompassing alternating phases of systole and diastole.

Electrocardiogram (ECG)

A diagnostic recording of the electrical activity of the heart over time, rather than its mechanical contraction.

P Wave

The deflection on an ECG tracing representing atrial depolarisation.

QRS Complex

The series of deflections on an ECG tracing representing ventricular depolarisation.

T Wave

The deflection on an ECG tracing representing ventricular repolarisation.

Atheroma

A fatty deposit that forms within an artery wall during the process of atherosclerosis.

Angina

Temporary chest discomfort caused by an inadequate oxygen supply to the heart muscle, typically provoked by exertion or stress.

Myocardial Infarction

A heart attack characterised by the damage or death of heart muscle tissue due to an inadequate blood supply.

Troponin

A blood biomarker released following heart muscle damage, used to help detect and diagnose myocardial infarction.

Referred Pain

Pain perceived at a site distant from the actual source of tissue damage due to shared sensory nerve pathways.

Cell

The basic unit of life; all living organisms are made of one or more cells.

Cell Theory

A biological principle stating that all life is made of cells, cells are the basic unit of life, and cells arise from pre-existing cells.

Specialised Cell

A cell adapted in structure and function to perform a particular role.

Stem Cells

Undifferentiated cells that can divide and develop into specialised cell types.

Eukaryotic Cell

A cell containing a distinct nucleus and membrane-bound organelles.

Prokaryotic Cell

A cell with no distinct nucleus or membrane-bound organelles, where DNA resides in an open region called the nucleoid.

Plasmids

Small circular DNA molecules, common in bacteria, that replicate independently of chromosomal DNA.

Nucleoid

The region of a prokaryotic cell that contains its main chromosomal DNA.

Nucleus

An organelle that contains DNA and regulates gene expression and cellular activities.

Gene Expression

The process of using information in a gene to synthesize a functional product, usually a protein.

Mitochondria

Organelles primarily responsible for aerobic respiration and the production of ATP.

Cristae

Folds of the inner mitochondrial membrane that increase surface area for cellular respiration.

Mitochondrial Matrix

The inner fluid-filled compartment of a mitochondrion containing enzymes, mitochondrial DNA, and ribosomes.

Adenosine Triphosphate (ATP)

An energy-carrying molecule utilised by cells to power metabolic processes.

Ribosomes

Cellular structures that serve as the site of protein synthesis.

Messenger RNA (mRNA)

RNA that carries genetic instructions transcribed from DNA to a ribosome for protein synthesis.

Transfer RNA (tRNA)

RNA molecules that carry specific amino acids to the ribosome during translation.

Transcription

The process of synthesizing mRNA from a DNA template; occurs in the nucleus in eukaryotic cells.

Translation

The process of decoding mRNA at a ribosome to assemble amino acids into a specific polypeptide or protein.

Rough Endoplasmic Reticulum (RER)

An organelle studded with ribosomes that synthesises, processes, and transports proteins.

Smooth Endoplasmic Reticulum (SER)

An organelle lacking ribosomes that synthesises and transports lipids.

Golgi Apparatus

An organelle composed of flattened cisternae that modifies, sorts, and packages proteins and lipids into vesicles.

Golgi Cisterna

A flattened, membrane-bound sac that constitutes a structural layer of the Golgi apparatus.

Cis Face of the Golgi

The receiving region of the Golgi apparatus that accepts transport vesicles arriving from the endoplasmic reticulum.

Medial Region of the Golgi

The middle cisternae of the Golgi apparatus where proteins and lipids undergo sequential modifications.

Trans Face of the Golgi

The shipping side of the Golgi apparatus that sorts and packages completed substances into vesicles destined for transport.

Protein Secretion Pathway

The sequential trafficking route of exported proteins: RER → transport vesicle → Golgi cis face → modification → Golgi trans face → secretory vesicle → cell membrane.

Lysosomes

Membrane-bound organelles containing enzymes that digest unwanted cellular materials and worn-out or damaged cell components.

Centrioles

Structures that organise microtubules and assist in forming the mitotic spindle during cell division.

Vacuoles

Cellular storage organelles involved in the regulation of ions, water balance, and intracellular pH.

Cytoskeleton

A network of protein fibres that supports cell shape, enables movement, facilitates division, and mediates intracellular transport.

Microfilaments

Cytoskeletal elements composed mainly of actin proteins that maintain cell shape and enable cellular movement.

Intermediate Filaments

Strong protein fibres that provide tensile strength, structural stability, and shape support to cells.

Microtubules

Hollow cylindrical tubes made of tubulin proteins that serve as tracks for transport, maintain cell shape, and form the mitotic spindle.

Lamins

Structural proteins that support the nuclear envelope and maintain the shape of the nucleus.

Phospholipid Bilayer

A double layer of phospholipids with hydrophilic heads facing water and hydrophobic fatty acid tails pointing inward.

Fluid Mosaic Model

A model describing biological membranes where phospholipids and some proteins move fluidly within the plane, scattered with diverse proteins.

Cell-Surface Antigens

Surface molecules recognized by the immune system to distinguish self from non-self cells.

Peptide Bond

A covalent chemical bond formed between amino acid monomers during condensation to build polypeptides.

Condensation

A chemical reaction that joins two molecules together with the accompanying removal of a water molecule.

Hydrolysis

A chemical process that cleaves molecular bonds through the addition of a water molecule.

Primary Protein Structure

The linear sequence of amino acids linked by peptide bonds in a polypeptide chain.