Cell Struture and Function- Chapter 4 Flashcards
Chapter 4
Cell Discovery
Discovered in 1665 by Robert Hooke.
Cell Theory
All organisims composed of cells
Smallest living things
Cells are the smallest living units.
Pre-existing cells
Cells arise only from existing cells.
Continuous Line of Descent
All cells trace back to first living cells.
Cell size limitation
Larger cells face diffusion challenges
Diffusion factors
Surface area, temperature, concentration gradient, distance
Advantage of small cells
More efficient than fewer, larger cells
Surface Area-to-Volume ration
Volume increases faster than surface area
Resolution
Minimum distance for distinguishing two points
Light Microscopes
Use visible light to magnify objects.
Resolution of light microscopes
Resolve structures 200 nm apart
Electron microsopes
Use electron beams for higher resolution
SEM
Scanning electron microscope for surface imaging
TEM
Transmission electron microscope for internal structures
Prokaryotic cells
Simplest cells, lack membrane-bound nucleus. Cell wall outside plasma membrane. Do not have ribosomes.
Bacteria cell walls
Composed of peptidoglycan for protection.
Eukaryotic cells
Complex cells with membrane-bound organelles
Cytoskeleton function
Supports and maintains cellular function
Nucleus
Contains genetic information
Nucleolus
Site of ribosomal RNA synthesis within the nucleus.
Nuclear Envelope
2 Phospolipid byliayers. Nuclear pores that control passage in and out.
Chromatin
Chromosomes + protein
Ribosomes
Makes protein across all cell types. To make protein, mRNA and tRNA is needed.
Ribosomal RNA (rRNA)
Protein-complex
Free Ribsomes
Synthesize proteins for cytoplasm and organelles.
Membrane-associated ribosomes
Synthesize proteins for the endomembrane system and export.
Endomembrane System
Network of membranes dividing cell into functional compartments.
Rough Endoplasmic Reticulum (RER)
Synthesizes proteins for secretion. Sent to lysosomes or plasma membrane.
Smooth Endoplasmic Reticulum (SER)
Involved in lipid synthesis and detoxification processes.
Golgi Apparatus
Packages and distributes molecules within and outside the cell.
Cis face
Receiving side of the Golgi apparatus for incoming vesicles.
Trans face
Shipping side of the Golgi apparatus for outgoing vesicles.
Lysosomes
Digestive vesicles that break down macromolecules and debris. Destroy cells or foregin matter that the cell has engulfed through phagocytosis.
Microbodies
Membrane-enclosed vesicles containing various enzymes.
Peroxisomes
Contain enzymes for fatty acid oxidation and detoxification.
Vacuoles
Larger membrane-bound structures for storage and transport.
Cental vacuole
Storage and maintenance of turgor pressure in plant cells.
Mitochondria
Powerhouse of the cell, responsible for energy production. Have their own DNA.
Chloroplasts
Contain chlorphyll for photosynthesis. Have their own DNA. Surrounded by 2 memebranes.
Thylakoids
Membranous sacs responsible for photosynthesis.
Grana
Stacks of thylakoids in chloroplasts
Membranes mitochondria are bound to…
- Outer membrane
- Intermembrane space
- Matrix
- Inner memebrane has cristae
Compartmentalization
Presence of nucleus and organelles in cells.
Endosymbiosis
Theory that organelles evolved from symbiotic cells.
Cyanobacteria
Single lineage of bacteria giving rise to chloroplasts
Binary Fission
A method of replication used by mitochondria
Microfilaments
Two protein chains loosely intertwined. Each part is actin.
Microtubles
Hollow tubes facilitating cell and material movement.
Intermediate filaments
Stable fibers between actin and microtubules. Prevent excess stretching of cells.
Centrosomes
Microtubule-organizing centers in animal cells. Plants and fungi lack this.
Cell movement
Movement tied to actin and microtubles
Flagella
Long structure with 9 + 2 microtuble arrangement.
Cilia
Shorter, numerous structures aiding in movement
Cell walls
Structures in plants and fungi, differing from prokaryotes.
Extracellular Matrix (ECM)
Animal cells lack this. Secrete and elaborate mixture of gylcoproteins into space arounds. Collagen may be abundant.
Integrins
Proteins linking ECM to cytoskeleton.
Tight Junctions
Prevent leakage between adjacent cell membranes.
Adhesive Juntions
Attach neighboring cell cytoskeletons.
Communicating Junctions
Allow signals to pass between cells
