Untitled Quiz

Study Notes

Mitochondria feature a smooth outer membrane and convoluted inner membrane, capable of self-replication; involved in cellular respiration.
The outer membrane contains porins and various enzymes, while the inner membrane is folded into cristae to increase surface area; the inner cavity, or matrix, holds mitochondrial DNA, ribosomes, and enzymes.
Energy production is facilitated through aerobic respiration in mitochondria, storing energy primarily as ATP.
Glycolysis occurs in the cytosol, producing pyruvate which migrates into mitochondria for further ATP synthesis; fatty acid metabolism is exclusively mitochondrial.

Composed of two rRNA subunits bound to proteins; can be either free in the cytoplasm or attached to the rough endoplasmic reticulum (rER).
Function to align mRNA with tRNA for the correct sequence of amino acids, catalyzing peptide bond formation.
Free ribosomes synthesize proteins for use within the cell, while those attached to rER produce proteins for export, lysosomes, and membrane proteins.

Begins with transcription, where pre-mRNA is synthesized as a complementary strand of DNA.
Post-transcription processing removes introns, transforming pre-mRNA into mature mRNA.
mRNA exits the nucleus and binds to ribosomes for translation, where it is read to produce proteins.

Ubiquitin tags damaged proteins, which are then directed to proteasomes or degraded by lysosomal enzymes.

Takes place in all cells, with fatty acids and triglycerides produced in the cytosol and cholesterol/phospholipids synthesized in the smooth endoplasmic reticulum (sER).
Lipid biosynthesis serves to replenish membranes, store energy, and maintain the continuity with the endoplasmic reticulum lumen.

The largest organelle, surrounded by a nuclear envelope that regulates genetic material storage, replication, and controls cell differentiation.
Contains nucleolus, a site for rRNA synthesis and ribosome assembly; changes size based on cellular activity.
DNA is organized into chromatin, with euchromatin being active and heterochromatin being inactive.

Rough ER is characterized by attached ribosomes, playing a critical role in protein synthesis, modification, and folding.
Smooth ER is involved in lipid synthesis, detoxification, and calcium ion storage; detoxifies drugs via cytochrome P450 in the liver.

Composed of membrane-bound cisternae that process and package proteins and lipids received from the rER.
Final assembly includes glycosylation of proteins and dispatching them to their destinations using SNARE proteins for targeting.

Contain hydrolytic enzymes active at low pH to degrade cellular debris and material taken in through endocytosis or phagocytosis.
Function in autophagy to remove damaged organelles and proteins.

Membrane-bound organelles containing oxidases and catalase, important for detoxifying substances and β-oxidation of fatty acids.
Produce hydrogen peroxide to kill pathogens and help synthesize bile acids in the liver.

Also known as plasma membrane; consists of an amphiphilic phospholipid bilayer embedded with proteins and cholesterol.
Functions to separate internal contents from the external environment, facilitate nutrient transport, and provide mechanical and chemical protection through the glycocalyx, which also aids in cell adhesion and signaling.