Cell Biology, Blood Physiology, and Homeostasis Review

Comprehensive vocabulary flashcards covering cell biology, biomolecules, blood physiology, hemopoiesis, hemoglobin degradation, blood groups, and homeostatic regulatory mechanisms.

Biochemistry

The science concerned with the chemical basis of life, the chemical constituents of living cells, and the reactions and processes that living organisms undergo.

Medical Biochemistry

A branch of biochemistry that deals specifically with the chemical basis of the human body.

Clinical Biochemistry

A sub-field of medical biochemistry dealing with clinical diseases and pathological conditions of the human body to support diagnosis, therapy, and research.

Branches of Biochemistry Hierarchy

The nested organizational framework showing Medical Biochemistry as a branch of Biochemistry, and Clinical Biochemistry as a specialized sub-branch within Medical Biochemistry.

Biomolecule-Disease Relationships

The physiological mapping connecting major biomolecules to specific pathological conditions: nucleic acids to genetic disease, proteins to sickle cell anemia, lipids to arteriosclerosis, and carbohydrates to diabetes mellitus.

Cytology

The branch of biology concerned with the study of structure, function, molecular organization, growth, reproduction, and genetics of cells; also called cell biology.

Modern Cell Theory

The core biological principle stating that all known living things are made of cells, the cell is the structural and functional unit of life, all cells arise from pre-existing cells by division, and cells contain hereditary information passed during division.

Anabolism

The metabolic process in which cells convert simple organic molecules into complex molecules.

Catabolism

The metabolic process involving the breakdown of complex molecules to release energy.

Chemotaxis

Cellular or organellar movement in response to chemical stimuli.

Phototaxis

Cellular or organellar movement in response to light stimuli.

Ribosomes

Cellular organelles responsible for synthesizing enzymes and other proteins, nicknamed "protein factories".

Golgi Apparatus

An organelle that chemically processes molecules received from the endoplasmic reticulum and packages them into vesicles; nicknamed the "chemical processing and packaging center".

Lysosomes

Small, membrane-bound organelles containing degradative enzymes that digest food compounds and macromolecules; nicknamed "digestive bags".

Mesosome

Inward folds of the plasma membrane in bacterial cells that carry associated respiratory enzymes in place of mitochondria.

Plasmid DNA

Short, circular DNA molecules in prokaryotes that replicate independently of the bacterial chromosome.

Tonoplast

The selective membrane bounding the fluid-filled vacuole in a plant cell.

Acid (Lewis Context)

According to the lecture text, a substance that can take up an electron pair to form a covalent bond.

Base (Lewis Context)

According to the lecture text, a substance that can donate an electron pair to form a covalent bond.

Condensation Reaction

A chemical process in which two molecules are combined into one molecule with the release of one water molecule ($A + B \rightarrow C + H_2O$).

Hydrolysis Reaction

A chemical process where a single complex molecule is cleaved into two smaller molecules by the addition of a water molecule ($C + H_2O \rightarrow A + B$).

Total Body Water (TBW)

The complete fluid content of the human body, accounting for approximately $60\%$ of total body weight in adults, $70\%$ in infants, and $50-55\%$ in elderly individuals.

Intracellular Fluid (ICF)

The fluid compartment contained within cells, comprising two-thirds ($40\%$) of total body water, where the principal cation is $K^+$ and principal anions are $HPO_4^{2-}$ and proteins.

Extracellular Fluid (ECF)

The fluid compartment outside cells, comprising one-third ($20\%$) of total body water, where the principal cation is $Na^+$ and principal anions are $Cl^-$ and $HCO_3^-Summary$.

Plasma

The liquid phase of blood comprising $55\%$ of total blood volume, composed of $90\%$ water, $7.1\%$ plasma proteins, $2\%$ organic substances, and $0.9\%$ inorganic electrolytes.

Serum

A clear straw-colored fluid separated from blood after clotting, similar in ionic composition to plasma but lacking fibrinogen.

Serum Albumin

The most abundant plasma protein ($4.7\,g/dL$) with a molecular weight of $69,000$, synthesized in the liver and essential for maintaining blood osmotic pressure.

Blood Fractionation Centrifugation

The separation of whole blood into distinct physical layers: plasma ($55\%$ total volume), buffy coat containing white blood cells and platelets ($<1\%$ total volume), and erythrocytes ($45\%$ total volume).

Haemopoiesis

The physiological process of blood cell formation from multipotent stem cells, occurring mainly in active bone marrow in adults.

Red Marrow

Active hemopoietic bone marrow present in all bones of children, but restricted in adults over age 20 to flat bones (sternum, ribs, vertebrae) and upper ends of long bones.

Proerythroblast

The earliest committed precursor stage in erythropoiesis, characterized by a very large cell size and nucleus, and an absolute absence of hemoglobin.

Reticulocyte

An immature, non-nucleated erythrocyte precursor containing residual organelles and high levels of synthesized hemoglobin before complete maturation.

Intrinsic Factor of Castle

A specialized glycoprotein required to complex with dietary Vitamin $B_{12}$ to enable its absorption across the distal ileum.

Ferritin

The primary intracellular protein complex used to store ferric iron safely in tissues, liver, spleen, and bone marrow.

Hemoglobin A (HbA)

The major adult hemoglobin form ($\approx 97.5\%$), composed of a globular chromoprotein containing four subunits ($2\alpha$ and $2\beta$ polypeptide chains) and four $Fe^{2+}$ atoms with a molecular weight of $68,000$.

Hemoglobin S (HbS)

An abnormal hemoglobin variant where valine replaces glutamic acid in the $\beta$ polypeptide chains, causing sickle cell anemia upon precipitation at low oxygen tension.

Biliverdin

A green bile pigment produced from the initial degradation and splitting of the heme complex of hemoglobin.

Bilirubin

A yellow bile pigment produced by the reduction of biliverdin, which travels to the liver to be conjugated into a water-soluble form before biliary excretion.

Erythrocyte Sedimentation Rate (ESR)

The rate at which red blood cells settle out of uncoagulated blood over time, averaging $4-6\,mm/hr$ in adult males and $6-10\,mm/hr$ in adult females.

Mean Corpuscular Volume (MCV)

A red blood cell index measuring the average physical volume of a single erythrocyte.

Polycythemia

An abnormal increase in total red blood cell count ($7-8 \text{ million}/mm^3$), causing increased hematocrit, blood volume, and blood viscosity.

Agglutinogens

Specific carbohydrate or protein antigens on the outer surface of erythrocyte cell membranes that determine blood group specificity.

Agglutinins

Specific antibodies ($\gamma$-globulins) dissolved in plasma that react against foreign red blood cell agglutinogens, leading to agglutination.

Erythroblastosis Fetalis

A hemolytic disease of the fetus or newborn resulting from maternal anti-D antibodies crossing the placenta to lyse $Rh^+$ fetal red blood cells in an $Rh^-$ mother.

Homeostasis

The physiological process coined by Walter B Canon in 1930 whereby dynamic internal conditions ($milieu\ interieur$) are maintained at equilibrium despite external variations.

Milieu Intérieur

The concept introduced by Claude Bernard defining the extracellular fluid internal environment in which multicellular cells live and function.

Baroreceptors

Sensory stretch receptors located within major arterial walls that detect blood pressure fluctuations and relay signals to the medulla oblongata.

Negative Feedback

The primary homeostatic control mechanism in which a system senses a deviation from a set point and triggers effectors to reverse or arrest the change back to baseline.

Positive Feedback

A homeostatic response mechanism in which the system amplifies and accelerates an initial stimulus in the same direction until an external endpoint is reached.

Parturition Loop

A positive feedback process during labor where cervical stretch triggers neural signals to the brain, stimulating oxytocin release from the posterior pituitary to cause progressively stronger uterine contractions.

Alveoli

Microscopic, thin-walled air sacs in the lungs where gas exchange occurs between inhaled oxygen and capillary blood carbon dioxide.