COPY: Biology Cells and Microscopy

Cell Nucleus

• The nucleus is the control center of the cell, housing genetic material (DNA).
• It regulates gene expression and mediates the replication of DNA during the cell cycle.

Electron Microscope

• The transmission electron microscope (TEM) and scanning electron microscope (SEM) utilize a beam of electrons for high magnification.

Total Magnification

• Total magnification power is calculated by multiplying the ocular lens power by the objective lens power (10x ocular × 50x objective = 500x total magnification).

Prokaryotic Cells

• Prokaryotic cells are characterized by the absence of a membrane-bound nucleus and organelles.

Lysosomes

• Lysosomes function as the cell's waste disposal system, breaking down macromolecules, old cell parts, and microorganisms.

Mitochondria

• Mitochondria are responsible for cellular respiration and ATP formation, providing energy for cellular activities.

Endoplasmic Reticulum

• The endoplasmic reticulum (ER) synthesizes proteins and lipids; it is involved in processing and transporting these molecules within the cell.

Types of Endoplasmic Reticulum

• The two types of endoplasmic reticulum are rough ER, which has ribosomes attached and is involved in protein synthesis, and smooth ER, which is involved in lipid synthesis and detoxification.

Ribosomes

• Ribosomes are the cellular structures where protein synthesis occurs, translating messenger RNA (mRNA) into polypeptides.

Apoptosis

• Apoptosis, or programmed cell death, is crucial for development, aiding in processes like tissue remodeling and removing damaged cells.

Prokaryotic vs. Eukaryotic Cells

• A primary distinction is that prokaryotic cells lack a true nucleus, while eukaryotic cells have a defined nucleus and membrane-bound organelles.

Scanning Electron Microscope (SEM)

• The SEM provides detailed 3D images of surfaces by scanning with a focused beam of electrons, enhancing surface topography visualization.

Energy Storage

• The organelle responsible for the majority of energy storage within a cell is the mitochondria, which produces and stores ATP.

Golgi Complex

• The Golgi Complex modifies, sorts, and packages proteins and lipids for secretion or delivery to other organelles, functioning as the cell's shipping center.

Organelle Handling Waste

• Lysosomes manage waste and damaged organelles, using digestive enzymes to degrade materials and recycle cellular components.