Cell Biology Concepts

Nondisjunction

Error in cell division where homologous chromosomes or sister chromatids fail to separate properly, leading to aneuploidy.

Polyploidy

Presence of more than two complete sets of chromosomes in a cell, often seen in plants and associated with developmental disorders in humans.

Inflammation

Body's response to injury or infection, characterized by acute and chronic phases involving different immune cells and mediators.

Cell Adaptation

Cellular responses to stress or changes, including atrophy, hypertrophy, hyperplasia, metaplasia, and dysplasia.

Meiosis

Specialized cell division process producing haploid gametes with genetic diversity through crossing over and independent assortment.

Neural Stem Cells

Multipotent cells in the nervous system capable of differentiating into neurons, astrocytes, and oligodendrocytes, crucial for neurodevelopment and repair.

Active Transport

Movement of molecules against their concentration gradient requiring energy, exemplified by processes like the sodium-potassium pump.

Diffusion

Passive movement of molecules from high to low concentration, essential for processes like gas exchange and nutrient uptake.

Osmosis

Diffusion of water through a selectively permeable membrane from low to high solute concentration, crucial for fluid balance.

Turner's Syndrome

Genetic disorder in females characterized by monosomy X, leading to various physical and reproductive abnormalities.

Fragile X Syndrome

Genetic disorder caused by CGG triplet repeat expansion on the X chromosome, resulting in intellectual disability and physical features.

Cystic Fibrosis

Autosomal recessive disorder affecting chloride channels, leading to mucus accumulation and impacting respiratory and digestive systems.

Huntington's Disease

Autosomal dominant neurodegenerative disorder caused by CAG repeat expansion in the HTT gene, leading to motor and cognitive symptoms.

Homologous Chromosomes

Chromosome pairs with the same genes, one from each parent, important for genetic diversity through recombination during meiosis.

Autosomal Recessive Disorders

Disorders requiring mutations in both alleles of a gene for manifestation, exemplified by conditions like cystic fibrosis.

Autosomal Dominant Disorders

Disorders manifesting with a mutation in one allele of a gene, such as Huntington's disease, with a 50% chance of inheritance.

X-linked Disorders

Disorders caused by mutations in genes on the X chromosome, including conditions like hemophilia A and Duchenne muscular dystrophy.

Epigenetic Effects

Heritable changes in gene expression that do not involve changes to the DNA sequence.

DNA Methylation

Addition of methyl groups to cytosine residues, often silencing gene expression.

Histone Modification

Post-translational modifications of histone proteins affecting chromatin structure and gene expression.

Immunopathology/Infection

The study of diseases related to the immune system and the effects of infections on the body.

Innate Immunity

Non-specific first line of defense including physical barriers, phagocytes, and innate immune proteins.

Active Immunity

Immunity acquired through exposure to antigens, leading to memory cell formation and long-lasting protection.

Passive Immunity

Transfer of antibodies from another individual providing temporary protection.

IgG

Most abundant antibody in circulation, conferring long-term protection and crossing the placenta.

IgM

First antibody produced during an immune response, effective at forming antigen-antibody complexes.

IgE

Antibody involved in allergic reactions and defense against parasitic infections.

Mast Cells

Cells that release histamine and other mediators contributing to inflammation and allergic responses.

Indirect Transmission

Transmission of infectious agents through an intermediary like a vector or fomite.

T Lymphocytes

Key players in cell-mediated immunity, including helper T cells and cytotoxic T cells.

B Lymphocytes

Responsible for humoral immunity, producing antibodies and memory B cells.

Urticaria

Also known as hives, characterized by red, itchy welts on the skin due to allergic reactions.

Eosinophils

Granulocytes combating parasitic infections and allergic reactions by releasing toxic proteins.

Neutrophils

Most abundant white blood cells, first responders to infection performing phagocytosis.

Monocytes

Blood cells that become macrophages and dendritic cells, key in phagocytosis and antigen presentation.

Leukotrienes

Lipid mediators produced by leukocytes, promoting inflammation and chemotaxis.

Natural Killer (NK) Cells

Lymphocytes that recognize and kill virus-infected cells and tumors without prior sensitization.

Basophils

Granulocytes involved in allergic reactions, releasing histamine and other mediators.

Acid-base Balance

Maintenance of the equilibrium between acid and base concentrations in the body.

Metabolic Acidosis

Acidosis caused by excess hydrogen ions or loss of bicarbonate, leading to decreased pH.

Metabolic Alkalosis

Alkalosis caused by loss of hydrogen ions or gain of bicarbonate, leading to increased pH.

Respiratory Acidosis

Acidosis due to decreased alveolar ventilation leading to CO2 retention.

Respiratory Alkalosis

Alkalosis due to increased alveolar ventilation leading to CO2 loss.

CO Poisoning

Poisoning caused by carbon monoxide binding to hemoglobin, impairing oxygen delivery.

Strangulation

Obstruction of air or blood flow in the neck leading to hypoxia.

Asphyxiation

Insufficient oxygen intake causing hypoxia, with symptoms like cyanosis and confusion.

Dehydration

Excessive loss of body water leading to symptoms like thirst and decreased urine output.

Tetanus Toxoids

Vaccines containing inactivated tetanus toxin to provide immunity against tetanus.