Concepts of Biology - Chapter 3: Cell Structure and Function

Flashcards for Concepts of Biology - Chapter 3: Cell Structure and Function

Prokaryotes

Simple cells without a nucleus.

Eukaryotes

Complex cells with a nucleus.

Light Microscopes

Microscopes that magnify cells up to approximately 400 times and are used in college biology labs.

Dissecting Microscopes

Microscopes with lower magnification used to examine larger objects like tissues.

Scanning Electron Microscope (SEM)

An electron microscope type that reveals surface details, uses metal coating, and produces 3D-like images.

Transmission Electron Microscope (TEM)

An electron microscope type that reveals internal structures, cross-sectional views, and produces high-resolution images.

Cell Theory - Principle 1

All living things are made of cells.

Cell Theory - Principle 2

Cells are the basic units of structure and function in living things.

Cell Theory - Principle 3

New cells are produced from existing cells.

Plasma Membrane

The protective outer layer surrounding the cell.

Proteins (in Plasma Membrane)

Gatekeepers that control the passage of substances in the cell membrane.

Microvilli

Finger-like projections that increase surface area for absorption.

Cytoplasm

The gel-like substance that fills the cell and houses organelles.

Cilia

Short, hair-like structures that can move in a wave-like motion for cellular locomotion.

Flagella

Longer, whip-like structures that can propel cells through fluid for cellular locomotion.

Nuclear Envelope

A double membrane that controls what goes in and out of the nucleus.

Rough Endoplasmic Reticulum (RER)

Network of connected tubes that assembles proteins and makes phospholipids (studded with ribosomes).

Smooth Endoplasmic Reticulum (SER)

Produces carbohydrates, lipids, steroid hormones, detoxifies substances, and stores calcium ions.

Vesicles (from ER)

Tiny membrane sacs that bud off from the ER and transport proteins and lipids.

Lysosomes

The cell's recycling center, containing powerful digestive enzymes.

Vesicles

Small, transport-focused sacs.

Vacuoles

Larger, storage-focused sacs; especially important in plant cells.

Ribosomes

Site of protein synthesis.

Mitochondria

Organelle responsible for energy production (ATP).

Peroxisomes

Organelles involved in detoxification and fatty acid breakdown.

Extracellular Matrix (ECM)

Consists of a network of substances secreted by cells, holding cells together and acting as a communication channel.

Plasmodesmata

Tiny channels that connect neighboring plant cells.

Tight Junctions

Seal the space between animal cells, preventing leaks.

Desmosomes

Hold animal cells together in tissues that need to stretch and flex.

Gap Junctions

Channels between animal cells that allow the exchange of ions and small molecules.

Phospholipids

Main building blocks of the plasma membrane, forming a double layer.

Cholesterol (in Plasma Membrane)

Keeps the plasma membrane fluid.

Carbohydrates (Sugars)

Help cells recognize each other in the plasma membrane.

Passive transport

Materials move down a concentration gradient from high to low concentration, without the cell using energy.

Diffusion

Small, uncharged molecules easily slip through the membrane's fatty core.

Facilitated Transport

Proteins embedded in the membrane act as channels or carriers for specific molecules.

Osmosis

Movement of water molecules across a semipermeable membrane from high to low concentration.

Active Transport

Requires energy (ATP) to move substances against their concentration gradient.

Electrochemical Gradient

Combines concentration and electrical forces.

Active Transport

Requires energy (ATP); Pumps and carrier proteins do the work; either directly or indirectly leverages energy.

Phagocytosis

Cell membrane surrounds the particle and pinches off to form an intracellular vacuole.

Pinocytosis

Cell membrane surrounds a small volume of fluid and pinches off, forming a vesicle.

Receptor-Mediated Endocytosis

Uptake of substances by the cell is targeted to a single type of substance that binds at the receptor on the external cell membrane.

Exocytosis

A vesicle migrates to the plasma membrane, binds, and releases its contents to the outside of the cell.