Bio150: Exam #2 Review Sheet Flashcards
What is the Surface Area-To-Volume Ratio?
As the cells size increase, the surface increases by a squared power and the volume increases by a cubed power.
What do Compound Microscopes do?
- Magnify in stages using several lenses
- Resolve structures by at least 200 nanometers
What do Transmission Microscopes do?
- Transmits electrons through material
- Resolves objects only 0.2 nanometers apart
What do Scanning Electron Microscopes?
- Beams electrons onto surface of specimen and reflect back
- Specimen amplifies and transmits the reflected electrons
- Yields 3D images
Facts about Prokaryotes.
- Encased in a Cell Wall
- All cellular functions occur within the same area in the cell (one room)
- Bacterial Cell Walls contain Peptidoglycan
- Archaean Cells Walls lack Peptidoglycan and have polysaccharides and proteins
- Move by flagella
- Instead of Nucleus there is a Nucleoid
Facts about Eukaryotes.
- Compartmentalized by the endomembrane system
- Supported by Cytoskeleton
- Has Nucleus
What occurs in the Nucleolus?
Intensive synthesis of ribosomal RNA.
What is the Nuclear Envelope?
The two phospholipid bilayer membranes that bind to the surface of the nucleus.
What are Nuclear Pores and what do they do?
- Structures that are scattered over the surface of the Nuclear Envelope
- Allow ions and small molecules to diffuse freely between nucleoplasm and cytoplasm
- Controls passage of proteins and RNA-protein complexes
Facts about Chromatins.
- They are composed by chromosomes that are organized with proteins
- Structure affects the function of DNA
Facts about Ribosomes.
- Composed of ribosomal RNA and Proteins
- Only function when actively synthesizing proteins
- Process requires messenger and transfer RNA
- They are the factories that make proteins
Facts about Endoplasmic Reticulum.
- Composed of a phospholipid bilayer embedded with proteins
- Two largest components are the Cisternal Space (Lumen) and Cytosol (fluid component of cytoplasm)
Rough Endoplasmic Reticulum Facts.
- Composed primarily of flattened sacs
- Surface is studded with ribosomes
- Proteins from here are exported to lysosomes, vacuoles, or plasma membrane
- Glycoproteins modify new proteins
Smooth Endoplasmic Reticulum Facts.
- Composed primarily of tubules
- Membranes are embedded with enzymes
- Enzymes create carbohydrates and lipids
- Steroid Hormones are made in SER as well
- Storage of Ca2+
- Ca2+ triggers muscle contraction and is used for signaling pathways
- Performs detoxification
Golgi Apparatus Facts.
- Composed of flattened stacks of membranes
- Stacks are called Cisternae
- Functions in collection, packaging and distribution of molecules
- Cis side of GA is the receiving end
- Trans side of GA is the shipping end
- Synthesizes cell wall components (non-cellulose polysaccharides)
Lysosome Facts.
- Digestive vesicles that arise from Golgi Apparatus
- Contain degrading enzymes that catalyze the rapid breakdown of organic molecules (proteins, lipid, carbohydrates and nucleic acids)
- Break down old organelles and recycles their components
- Function in acid pH and activated by phagocytosis of food vesicles
Peroxisomes Facts.
- Contains enzymes that oxidize fatty acids
- The enzyme “Catalase” breaks down hydrogen peroxide to make it harmless
What is the Tonoplast?
The membrane surrounding the Central Vacuole that determines the cells tonicity (osmotic balance).
Mitochondria Facts.
- Typically tubular or sausage-shaped found in Eukaryotic Cells
- Bound by smooth outer membrane and inner folded membrane with Cristae
- Cristae contains matrix and intermembrane space
- Have their own DNA
- Participates in Oxidative Metabolism
- Mitochondria divides on its own accord
Chloroplast Facts.
- Make their own food
- Contain chlorophyll (green pigment)
