1.2 Cell Structure and Function

The primary component of most cells, constituting 70-85% of their mass.

Essential minerals found within cells, playing critical roles in various cellular processes.

The second most abundant substance in cells, primarily responsible for structural support and enzymatic activity.

A group of substances that dissolve in organic solutions rather than water, including phospholipids and cholesterol.

A vital component of cell membranes, forming a barrier that separates intracellular and extracellular environments.

A type of lipid that helps maintain membrane fluidity and stability.

Specialized structures within cells responsible for specific functions, often enclosed by membranes.

A thin, flexible barrier surrounding the cell, composed mainly of proteins and lipids, regulating the passage of substances.

A network of protein filaments found in cells, providing structural support, allowing for movement, and playing a role in cell division.

Fibrous proteins that form long chains, contributing to cell shape and movement. They're involved in muscle contraction.

Strong, rope-like filaments that provide strength and support to the cell, working in conjunction with microtubules. They are found in all cell types.

Hollow tubes made of tubulin that act as a structural component of the cytoskeleton, involved in cell division, and providing tracks for organelle movement.

The cell's control center, containing DNA and directing cellular activities like growth, replication, and death.

A double-layered membrane surrounding the nucleus, regulating the passage of molecules in and out.

Openings in the nuclear envelope that allow for selective exchange of molecules between the nucleus and the cytoplasm.

The process by which substances move across the cell membrane from a region of higher concentration to a region of lower concentration.

The process by which substances move across the cell membrane against their concentration gradient, using energy.

The process by which large particles are taken into a cell through an inward folding of the cell membrane.

A type of endocytosis where the cell engulfs small particles.

A type of endocytosis where the cell engulfs large particles or even whole cells.

Small, membrane-bound organelles responsible for breaking down cellular waste products and damaged organelles.

The process of a cell breaking down its own internal components for recycling or disposal.

A network of folded membranes within the cytoplasm, involved in protein synthesis, lipid synthesis, and detoxification.

Small, membrane-bound sacs that transport materials within a cell, often from the endoplasmic reticulum to the Golgi apparatus.

The process of converting glucose into pyruvate in the cytoplasm of the cell.

A molecule that serves as the primary energy currency of cells. It stores energy in high-energy phosphate bonds that can be broken to release energy.

A type of cell movement that occurs in amoebas and some white blood cells, characterized by a crawling-like motion.

Hair-like structures on the surface of cells that can beat rhythmically to move fluids or particles.

A substance that attracts or repels cells, causing them to move towards or away from it.

The movement of a cell towards a chemical attractant.

The movement of a cell away from a chemical repellent.

The process of energy production in the mitochondria using oxygen, resulting in the formation of ATP.

The main source of ATP production in cells.

A molecule that is a product of glycolysis and enters the mitochondria for further energy production.

A critical molecule involved in the Krebs cycle that is formed from pyruvate.

A series of chemical reactions that occur in the mitochondria, breaking down carbon compounds and releasing energy for ATP synthesis.

The plasma membrane is a thin, flexible barrier that surrounds the cell and controls what enters and exits. It is composed of a phospholipid bilayer with embedded proteins.

A phospholipid is a molecule that has a hydrophilic head (attracted to water) and a hydrophobic tail (repelled by water). This structure forms the basis of the plasma membrane.

Integral proteins are embedded within the phospholipid bilayer of the cell membrane, while peripheral proteins are attached to the surface of the membrane.

Integral proteins provide channels for substances to move across the membrane, act as carriers for transport, act as active transport carriers, and serve as receptors for signals.

Carbohydrates attached to proteins or lipids on the outer surface of the cell membrane form the glycocalyx. It acts as a protective layer, helps with cell recognition, and provides binding sites for hormones.

The rough ER has ribosomes attached to its surface, which are sites of protein synthesis. It is responsible for producing proteins that will be exported from the cell or used in other cellular compartments.

The smooth ER lacks ribosomes. It is involved in lipid and steroid synthesis, detoxification, and calcium storage.

The Golgi apparatus is a stack of flattened sacs called cisternae. It modifies, sorts, and packages proteins and lipids produced by the ER.

Peroxisomes are organelles that contain enzymes involved in detoxification reactions and lipid metabolism. They utilize hydrogen peroxide to oxidize substances.

The inner membrane of the mitochondria is highly folded into cristae, providing a large surface area for the enzymes involved in ATP production to operate.

ATP (adenosine triphosphate) is the primary energy currency of the cell. It is used to power various cellular processes, such as muscle contraction, nerve impulse transmission, and protein synthesis.