The Cellular Level of Organization

These flashcards cover key terms and definitions related to the cellular level of organization, essential for understanding cellular biology.

Cell

The basic unit of life.

Cytology

The study of cells and their functions.

Homeostasis

Maintenance of a stable internal environment within a cell.

Robert Hooke

The scientist who first observed and named 'cells'.

Anton van Leeuwenhoek

The scientist who first observed living, moving cells.

Cell Membrane

Also known as the plasma membrane, it surrounds the cell.

Phospholipid Bilayer

The main structural component of the cell membrane.

Hydrophilic Head

The part of the phospholipid that is attracted to water.

Hydrophobic Tails

The two fatty acid tails of phospholipids that repel water.

Cholesterol

A substance that helps maintain fluidity within the cell membrane.

Integral Proteins

Proteins that are embedded within the cell membrane.

Peripheral Proteins

Proteins that attach to the surface of the cell membrane.

Glycocalyx

A carbohydrate and protein structure for cell recognition on the cell membrane.

Selectively Permeable

A property of the cell membrane that allows certain substances to pass through.

Passive Transport

Movement of substances from high to low concentration without energy.

Simple Diffusion

The movement of oxygen and carbon dioxide across the cell membrane.

Facilitated Diffusion

The process of using channel or carrier proteins to move substances across the membrane.

Osmosis

The diffusion of water across a selectively permeable membrane.

Hypotonic Solutions

Solutions that cause cells to swell.

Hypertonic Solutions

Solutions that cause cells to shrink.

Active Transport

Movement of substances against their concentration gradient requiring energy.

Sodium-Potassium Pump

A transport mechanism that moves sodium out and potassium into the cell.

Endocytosis

The process of bringing materials into the cell.

Exocytosis

The process of removing materials from the cell.

Phagocytosis

The process by which a cell engulfs solid materials.

Pinocytosis

The process by which a cell engulfs liquid materials.

Cytoplasm

The material within the cell membrane, excluding the nucleus.

Rough Endoplasmic Reticulum (ER)

The part of the ER that synthesizes proteins.

Smooth Endoplasmic Reticulum (ER)

The part of the ER that synthesizes lipids and detoxifies substances.

Golgi Apparatus

An organelle that modifies and packages proteins.

Lysosomes

Organelles containing digestive enzymes.

Mitochondria

Organelles that produce ATP through cellular respiration.

Peroxisomes

Organelles that detoxify substances like hydrogen peroxide.

Cytoskeleton

A network of fibers that help maintain cell shape and aid movement.

Centrioles

Structures important for cell division.

Interphase

The phase of cell growth and DNA replication.

Mitosis

The process of cell division.

Apoptosis

Programmed cell death.