General Bio I Lecture 4 (Part 2): Cell Structure and Function

Endoplasmic Reticulum

A mesh like membrane system found within cytoplasm connected to the nuclear envelope. Essential for synthesis, folding, modifications, and transportation of proteins and lipids.

Rough ER

Endoplasmic Reticulum that has tubules studded with ribosomes and is the site of protein synthesis

Smooth ER

Endoplasmic reticulum that has smooth tubules and is a site for lipid and membrane production

Vesicles

Small membrane pockets made of phospholipids for transporting, storing, and digesting materials

Golgi Apparatus

Made of many flattened lipid sacks and vesicles. Processes, sorts, and transports proteins to the cell surface or to lysosomes (to continue processing)

Lysosomes

Organelle derived from the Golgi Apparatus filled with digestive (hydrolytic) enzymes to breakdown molecules, bacteria, and worn-out cell parts. If ruptured it can cause denaturation due to acidic ph.

Mitochondria

A double membrane organelle that is the cells power station since it converts glucose and oxygen into ATP. Has its own DNA and ribosomes.

Cristae

Folding in the mitochondrion that increases the surface area for ATP synthase enzymes

Matrix

Center area of the mitochondrion that contains its enzymes, DNA, and ribosomes.

Endosymbiotic Theory

The belief that the mitochondrion used to be a bacterium that joined a larger cell for protection in exchange for ATP production.

Peroxisomes

Organelle found in the cytoplasm. Digestive enzyme oxidase that uses oxygen to breakdown other molecules by removing electrons that are later transferred to oxygen making Hydrogen peroxide, results in water and oxygen.

Hydrogen Peroxide

A byproduct from oxidase inside the peroxisome that is converted to water and oxygen. Is dangerous as it can cause damage to proteins, lipids, and DNA.

Vacuole

A plant cell storage organelle that stores water, enzymes, waste, and helps maintain cell structure

Plastids

Membrane bound organelles found in plants and algae needed for nutrition synthesis (production & storage), photosynthesis, and pigment

Chloroplasts

Plastid that has the ability to convert sunlight into energy through photosynthesis and stored as starch

Cytoskeleton

A network of protein filaments that work as the internal framework that anchor junctions

Microfilaments

Give cells the ability to stretch, compress, flexible, and adaptable for movement (structural support).

Intermediate Filaments

Allow the cell to maintain its shape, anchor organelles (nucleus and mitochondrion), and helps bind cells together

Microtubules

Works as mediator for cell division, chromosome separation for the cell and creates roads for Kinesin movement.

Cilia

Hair like organelle with a structural core made of microtubules that provides the cell with movement, transportation, and sensory functions.

Flagella

Hair like appendage made of microtubules that provides a cell with movement and sensory ability

Protein Pathway

Peroxisomes in Detoxification

The ability to neutralize harmful waste and breakdown fatty acids and amino acid to keep cells safe

Taxol

Stops the rearrangements of microtubules, stopping chromosomes separation. Used to treat ovarian, breast, lung, and Kaposi’s sarcoma cancer.

Cell Junctions

Internal scaffolding that connects cells to each other to ensure support, selective barriers, and communication.

Tight Junctions

proteins that seal and connect to actin filaments to control transporting and maintain cell polarity

Anchor Junctions

proteins that hold cell together by attaching to actin and intermediate filaments for strength

Gap Junctions

intercellular channels that connect to other cells for the transportation of molecules and communication.

Glycoproteins

Proteins linked to carbohydrate chain used for cell communication. immunity, and molecular recognition located on the cell membrane

Glycolipids

molecules composed of carbohydrates that attaches to lipids for membrane stability and cellular recognition

White Blood Cell

Can produce long and thin extensions that can reach and engulf pathogens due to microfilaments

Cytoplasm

A site for protein synthesis as ribosomes are able to turn mRNA into protein.

Intestine cells

The empirical cells form a strong, tight, and communicative sheet for absorption and protection through the cytoskeletons internal scaffolding