Cell Structures and Functions

These flashcards cover key concepts and vocabulary related to cell structures and functions, facilitating review and understanding of biological processes.

Cell Theory

The fundamental concept that all living things are made of cells, all cells come from other living cells, and the cell is the basic unit of life.

Eukaryotic Cells

Cells that have a nucleus enclosed within membranes, along with membrane-bound organelles.

Prokaryotic Cells

Simpler cells that lack a nucleus; DNA is located in a nucleoid region.

Ribosomes

Complexes made of rRNA and protein that are the sites of protein synthesis.

Mitochondria

Organelles known as the powerhouse of the cell, where cellular respiration occurs to produce ATP.

Chloroplasts

Organelles that capture light energy to perform photosynthesis in plants and algae.

Plasma Membrane

The selective barrier that controls what enters and leaves the cell, composed of a phospholipid bilayer.

Endomembrane System

A system of membranes in the cell that regulate protein traffic and perform metabolic functions.

Lysosomes

Membranous sacs of hydrolytic enzymes that digest macromolecules.

Cytoskeleton

A network of fibers that organizes the cell's structure and activities, providing support and shaping the cell.

Active Transport

The movement of molecules against their concentration gradient, requiring cellular energy (ATP).

Facilitated Diffusion

A process by which molecules pass across the membrane through cell membrane channels.

Osmosis

The diffusion of water across a selectively permeable membrane.

Isotonic Solution

A solution with a solute concentration equal to that inside the cell, resulting in no net movement of water.

Hypertonic Solution

A solution with a higher solute concentration than inside the cell, causing the cell to lose water and shrink.

Hypotonic Solution

A solution with a lower solute concentration than inside the cell, causing the cell to gain water and swell.

Phagocytosis

A form of endocytosis where a cell engulfs solid particles, forming a food vacuole.

Exocytosis

The process of moving substances out of the cell by vesicles fusing with the plasma membrane.

Vacuoles

Storage organelles in cells that can hold water and other substances; larger in plant cells.

Cell Wall

A rigid structure that surrounds the plasma membrane in plant cells, providing support and protection.

Rough ER

Has ribosomes. Responsible for making (secreting) glycoproteins, distributes transport vesicles, membrane factory for the cell

Smooth ER

Lacks ribosomes, tubular structure. Functions to synthesize(makes) lipids, detoxifies poisons, stores calcium ions

Nucleolus

chromatin and ribosome subunits

Nuclear Envelope

Surrounds nucleus with a pore structure to let things in and out

nuclear lamina

part of the nuclear envelope that is made of proteins and maintains the shape of the nucleus

chromosomes

what DNA is organized into in the nucleus

chromatin

One DNA molecule associated with proteins

Vesicles

membranous sac that carries, stores, and transports substances

Food vacuoles

stores food formed by phagocytosis

Central vacuoles

Stores waste and sap (PLANTS)

Contractile Vacuole

Store water and pumps out excess water out of cells

Endosymbiont Theory

The cell engulfed living bacteria (mitochondria and chloroplasts) and they functions within the cell and help it out

Peroxisomes

membrane bound sacs that break down fats, detoxify harmful substances, converts fatty acids to sugars (glyoxysomes)

Microtubules

Thickest (element of cytoskeleton) shapes the cell, guides movement of organelles, separates chromosomes during cell division

Intermediate Filaments

Medium sized, most permanent of filaments, supports cell shape, and fixes organelles in place

Microfilaments

Smallest filament, supports the cells shape, and aids in movements

Myosin’s

motor protein that allows cells to move

Cortex

network of microfilaments that supports the cells shape

pseudopodia

cellular extension that allows the cells to move

Cytoplasm is Streaming

circular flow of cytoplasm driven by actin and protein interactions (PLANT)

Actin

protein that forms microfilaments

Cholesterol

In the cell membrane and offers support and flexibility

Extracellular Matrix (ECM)

made of glycoproteins (collagen, proteoglycans and fibronectin). Regulates cell behavior, influence the activity of genes ANIMAL

Plasmodesmata

The channel that connects PLANT cells

Tight junctions

Prevent extra fluid leakage

Desmosomes

Anchoring junctions

Gap junctions

communication junctions

Cilia

extension of a cell found in large numbers and moves back and fourth (think oars) moves the cell

Flagella

cell extension that propels the cell forward. Found a few per cell and moves forward (like a tail)

Centrosomes

Found in the nucleus of an ANIMAL cell and organizes microtubules, crucial for cell division

Centriole

Pair of centrioles for a centrosomes

fluid mosaic model

Model of the cell membrane. The phospholipids are flexible (therefore fluid) and proteins and placed in the cell membrane to aid with transportation (therefore mosaic)

Proteins (in cell membrane)

help substances cross through the cell membrane

Carbohydrates (Cell membrane)

Identifications tags for cells

Selective Permeability (Cell membrane)

Certain things can pass though the cell membrane but other things cannot

Tonicity

the ability of a solution to gain or lose water

Sodium potassium pump

Pump that moves ions in and out of the cell. Moves potassium in and sodium out