Cells- Unit 2 Final Prep

Cell Membrane

Plasma membrane surrounding the cell, regulating entry.

Fluid Mosaic Model

Describes cell membrane structure with embedded proteins.

Phospholipid Bilayer

Two layers of phospholipids forming the cell membrane.

Hydrophobic Tails

Fatty acid groups that repel water.

Hydrophilic Heads

Phosphorous groups that attract water.

Integral Proteins

Proteins embedded within the phospholipid bilayer.

Peripheral Proteins

Proteins attached to the membrane surface.

Glycoproteins

Proteins with carbohydrate chains, acting as identity factors.

Selectively Permeable

Membrane allowing certain substances to pass.

Passive Transport

Movement across membrane without energy input.

Diffusion

Movement from high to low concentration until equilibrium.

Osmosis

Diffusion of water across a selectively permeable membrane.

Facilitated Diffusion

Transport of molecules via protein channels, no energy.

Active Transport

Movement against concentration gradient, requires ATP.

Na+/K+ Pump

Active transport mechanism maintaining ion balance in cells.

Osmotic Pressure

Pressure from water movement across a membrane.

Concentration Gradient

Difference in concentration of substances across a space.

Phagocytosis

Cell engulfs large particles or cells.

Pinocytosis

Cell takes in small particles or liquids.

Aquaporins

Channel proteins facilitating water transport in cells.

Equilibrium

State where concentrations are equal across a membrane.

Cell Fingerprints

Unique surface molecules identifying cells to the immune system.

Carrier Proteins

Proteins that facilitate molecule transport across membranes.

Endocytosis

Process of taking in molecules by membrane invagination.

Exocytosis

Process of expelling substances from a cell.

Isotonic Solution

Equal solute concentration inside and outside the cell.

Hypertonic Solution

Higher solute concentration outside, causes cell shrinkage.

Crenation

Shrinking of animal cells in hypertonic solutions.

Hypotonic Solution

Lower solute concentration outside, causes cell swelling.

Lysis

Bursting of cells in hypotonic solutions.

Turgor Pressure

Pressure from water inside plant cells, maintains rigidity.

Plasmolysis

Separation of cell membrane from cell wall in plants.

Bulk Transport

Movement of large quantities of molecules across membranes.

Cell Pumping

Active transport mechanism to move ions across membranes.

Conformational Change

Structural change in proteins during transport processes.

ATP Hydrolysis

Energy release from ATP breakdown for active transport.

Vesicle Fusion

Process where vesicles merge with cell membranes.

Surface Area to Volume Ratio

Ratio affecting cell size and efficiency.

Cell Volume Formula

Volume calculated as v=l•w•h.

Surface Area Calculation

SA calculated as L-W x all sides.

Cell Size Limitation

Larger volume increases faster than surface area.

Shape Adaptation

Cells change shape to increase surface area.

Alveoli Function

Increase surface area for gas exchange in lungs.

Microvilli Role

Enhance absorption in intestinal cells.

Mitochondria Structure

Site of energy production in cells.

Diffusion Definition

Movement from high to low concentration.

Osmosis Definition

Water movement through a semipermeable membrane.

Facilitated Transport

Passive transport using protein channels.

Exocytosis Definition

Process of expelling materials from a cell.

Endocytosis Definition

Process of taking materials into a cell.

Prokaryotic Cells

Simple cells without a nucleus or organelles.

Eukaryotic Cells

Complex cells with a nucleus and organelles.

Cell Theory

All living organisms are made of cells.

Electron Micrograph

Image used to identify organelles in cells.

Mitochondria

Powerhouse of the cell, produces ATP.

Chloroplasts

Site of photosynthesis in plant cells.

Nucleus

Control center, contains genetic material.

Ribosomes

Small structures for protein synthesis.

Endoplasmic Reticulum (ER)

Network of membranes for protein and lipid synthesis.

Rough ER

Studded with ribosomes, modifies proteins.

Smooth ER

Lacks ribosomes, synthesizes lipids.

Golgi Apparatus

Processes, packages, and distributes proteins.

Lysosomes

Contains digestive enzymes for waste breakdown.

Vesicles

Small membrane-bound transport sacs.

Vacuoles

Storage sacs for nutrients and waste.

Cytoskeleton

Network providing structural support to cells.

Centrioles

Involved in cell division, organizing microtubules.

Cell Wall

Rigid outer layer in plant cells.

Nuclear Envelope

Double membrane surrounding the nucleus.

Chromatin

DNA and protein complex in the nucleus.

Nucleolus

Site of ribosome production within the nucleus.

Polysomes

Clusters of ribosomes translating mRNA simultaneously.

Thylakoids

Membrane-bound structures in chloroplasts for photosynthesis.

Stroma

Fluid-filled space in chloroplasts surrounding thylakoids.

Endoplasmic Reticulum (Rough)

Studded with ribosomes, synthesizes proteins.

Endoplasmic Reticulum (Smooth)

Lacks ribosomes, synthesizes lipids and detoxifies drugs.

Cytoplasm

Gel-like substance where organelles are suspended.

Centriole

Short cylinders aiding in cell division and organization.

Microtubules

Cytoskeletal components maintaining cell shape and structure.

Peroxisomes

Contain enzymes for breaking down fatty acids and detoxification.

Plastids

Organelles involved in the synthesis and storage of food.

Basal Bodies

Organizing centers for cilia and flagella formation.

Cilia

Short hair-like structures aiding in cell movement.

Flagella

Long whip-like structures for cell motility.

Chloroplast

Converts light energy into chemical energy.

Vacuole

Stores water, nutrients, and waste in cells.

Microvilli

Projections increasing surface area for absorption.