cells

Cell membrane

Thin layer surrounding cell controls what entersl. Made of double layer of lipids

Cytosol

Jelly substance in cell that helps with chemical reactions.

Organelle

Type of membrane wrapped body in cell that does something specific

Endomembrane system

Endoplasmic reticulum, Golgi apparatus, vesicles. They work together to produce package and store cellular products

endoplasmic reticulum (ER)

passage through cells for transporting, making and sorting material. made of lipid

Rough ER

dotted with ribosomes. makes proteins that become cell membrane or get sent out.

what does ER stand for

endoplasmic reticulum

SER

smooth with no ribosomes, makes lipids, stores Ca++, in cells that produce lots of hormones, breaks down toxins, uses carbohydrates

ribosome

organelle that produces proteins

Mrna

a message made from dna. Used by ribosomes to build proteins and Gets broken down after use. “recipe for protein”

lipids

fats used for energy, building cell membrane, and insulation

Ca++

calcium ion helps with muscle contraction, nerve signaling, blood clotting, and building strong bones. acts like a switch that turns processes on and off

carbohydrates

sugars and starches used for quick energy

glycosylation

adds carbohydrates (sugars) to proteins or lipids, helping them work right

Cytoskeleton

The cell’s “skeleton” that gives shape, helps movement, division, and transports stuff inside the cell.

parts of cytoskeleton

• Microtubules (thickest)

• Microfilaments (thinnest)

• Intermediate filaments (middle)

microtubules

Thick tubes made of tubulin; keep cell shape, move things, help cell division.

what do microtubules do

Act like “railroad tracks” that pull chromosomes apart

cilia

Tiny hair-like structures that beat to move mucus, dust, bacteria, or egg cells

flagella

Long tail for movement; only human cell with one is sperm

centrioles

Microtubule structures that help organize microtubules and assist in cell division

microfilaments

Thinnest fibers made of actin; help with movement and cell shape

actin and myosin

Work together to make muscles contract

intermediate filaments

Medium-sized fibers made of keratin; provide strength and resist pulling forces.

what do intermediate filaments do

Anchor organelles and help cells stick together.

Microtubules vs Microfilaments vs Intermediate Filaments

• Microtubules = big tubes, movement + division

• Microfilaments = tiny threads, muscle + cell splitting

• Intermediate filaments = tough ropes, strength + stability

Golgi apparatus

Sorts, modifies, and ships products from the RER; like a post office

vesicles from Golgi

Carry products to membrane for export or to form lysosomes.

lyosome

Contains digestive enzymes; breaks down old cell parts and foreign material

autophagy

Cell digests its own damaged parts.

Autolysis

Lysosomes release enzymes to kill a damaged cell (controlled cell death).

cristae

Folded inner membrane where ATP-producing reactions occur.

mitochondria

Energy transformers”; make ATP through cellular respiration

ATP

Main energy molecule used by cells.

cells with lots of mitochondria

Muscle cells and neurons (high energy needs)

peroxisomes

Detoxify chemicals; break down lipids; produce and neutralize H₂O₂.

peroxisome vs lysosome

Peroxisomes detoxify; lysosomes digest.

reactive oxygen species (ROS)

Highly reactive oxygen molecules that can damage cells.

examples of ros

OH (hydroxyl radical), H₂O₂, O₂⁻ (superoxide).

why is ROS dangerous

They steal electrons → damage DNA, proteins, lipids, carbs, Oxidative stress

Antioxidants

Neutralize ROS by being oxidized themselves.