Cell Physiology and Structure

These flashcards cover key terms and concepts from the lecture on cell physiology and structure, focusing on cell components, functions, and associated diseases.

Cell

The basic structural and functional unit of life, which can be unicellular (like amoebas) or multicellular (like humans, animals, and plants).

Plasma membrane

The outer thin and flexible membrane of the cell that separates intracellular from extracellular compartments.

Cytoplasm

The cellular region between the nucleus and plasma membrane, containing cytosol, organelles, and inclusions.

Phospholipids

The most abundant lipids in the plasma membrane, with hydrophilic heads and hydrophobic tails.

Integral proteins

Proteins that extend entirely through the plasma membrane and can act as receptors.

Peripheral proteins

Proteins located mainly on the cytoplasmic side of the membrane that support its structure.

Glycocalyx

A sugar covering or cell coat formed from carbohydrates projecting out from glycoproteins or glycolipids, aiding in cell recognition.

Passive transport

Movement of substances across the plasma membrane without the use of energy, moving down the concentration gradient.

Active transport

Movement of substances against a concentration gradient, requiring energy (ATP) to transport molecules.

Endocytosis

The process of bringing large molecules into the cell by engulfing them in vesicles formed from the plasma membrane.

Exocytosis

The process by which membrane-lined cytoplasmic vesicles fuse with the plasma membrane and release their contents outside the cell.

Phagocytosis

A type of endocytosis where the cell engulfs large particles, forming a phagosome.

Pinocytosis

A type of endocytosis also known as 'cell drinking', where the cell takes in small amounts of extracellular fluid.

Receptor-mediated endocytosis

A selective process in which specific molecules are brought into the cell after binding to receptors on the membrane.

Mitochondria

Rod-shaped organelles responsible for ATP synthesis, often referred to as the cell's powerhouses.

Lysosomes

Membrane-walled sacs containing digestive enzymes that perform intracellular digestion.

Golgi apparatus

A stack of membranes that modifies, sorts, and packages proteins and lipids for secretion or use within the cell.

Rough Endoplasmic Reticulum (rER)

An organelle studded with ribosomes involved in synthesizing proteins for secretion or for the cell membrane.

Smooth Endoplasmic Reticulum (sER)

An organelle involved in lipid synthesis, lipid metabolism, and detoxification that lacks ribosomes.

Cytoskeleton

A network of rods that supports cellular structure and facilitates cell movement.

Microtubules

Cylindrical structures made of tubulin that help maintain cell shape and transport organelles.

Microfilaments

Fine filaments made of actin that are involved in muscle contraction and cellular movement.

Centrioles

Cylindrical structures that organize microtubule formation during cell division and form bases of cilia and flagella.

Familial hypercholesterolemia

An inherited condition that results in high cholesterol levels due to lack of receptors for LDL.

Gaucher’s disease

An inherited condition caused by lack of an enzyme that leads to harmful substance accumulation in the body.

Tay-sachs disease

An inherited disease characterized by a deficiency in lysosomal enzymes leading to dangerous accumulations in nerve cells.