Cells, Plasma Membrane, and Mitosis Exam Flashcards
Exocytosis
- Active Transport
* Materials are expelled or secreted by the cell
Endocytosis
- Active Transport
* Large particulates enter the cell
Hypertonic Solution
- Releases water
* Cell shrinkage
Isotonic Solution
*Water flowing in and out
Hypotonic Solution
- Water diffusing in
* Cell becoming “hippo”
Cancer
Uncontrolled cell division and death caused by the interaction between environmental factors and changes in the production of enzymes involved in the cell cycle
Tumor
A mass that forms within otherwise normal tissue, caused by the controlled growth of a transformed cell
Angiogenesis
Formation of blood vessels which grow toward a tumor
Metastases
The spread of cancer beyond its original site
Benign
A tumor that is not able to spread
Malignant
A tumor with the ability to spread
Glycerol Base
The backbone of a phospholipid
Polar Head
attracted to water
Unsaturated vs. saturated fatty acids
Saturated-straight
Unsaturated-bent, double bond, more fluid
Phospholipids
*Glycerol, 2 fatty acids, phosphate group
Osmosis
The diffusion of water
Dynamic Equilibrium
- Continuous movement, no overall change in concentration
* Required to maintain homeostasis
Turgor Pressure
- Internal cell pressure
- Gives shape and support to plants
- Plant will wilt when it loses turgor pressure
Plasmolysis
- Causes plant to wilt
* Plasma membrane shrinks away from cell wall
Selective permeability
- Only certain substances can pass through the plasma membrane
- Required to maintain homeostasis
Concentration Gradient
Difference in concentration of a substance across space
3 Microscopes
SEM and TEM Microscopes are electron microscopes
SEM
3D, up to 60000x zoom, pass over the surface
TEM
2D, hundreds of thousands of times zoom, pass through an object
Compound-Light
Can be used on living organisms, series of lenses, light passed through object through lenses
Active and Passive Transport
Active-Requires energy, goes agains concentration gradient
Passive-no energy required
Schleiden
All organisms are composed of one or more cells. Plants-Schleiden down the hill
Schwann
The cell is the basic unit of organization of organisms. Schwann-swan <–animals
Hooke
Examined the cork.
Compound-light microscope
Named “cells”
Virchow
All cells come from pre-existing cells. Maggots in meat
Leeuwenhoek
Scraped teeth
The Cell Theory (Three Parts)
1) All organisms are composed of one or more cells. -Shleiden
2) The cell is the basic unit of organization of organisms. -Schwann
3) All cells come from pre-existing cells. -Virchow
Prokaryotic Cells
Cells that lack a nucleus or membrane-bound internal organelles
Eukaryotic Cells
1) Cells containing a nucleus & membrane bound internal organelles
2) Structure allows for cell specialization.
Interphase
- Cell growth period
- Centrioles replicate
- Chromosomes copies
Prophase
- Longest phase
- Chromatin–>chromosomes
- Chromosomes made of sister chromatids<–held together by a centromere
- Nuclear fizzilage
Metaphase
Metaphase-middle
Chromosomes attach to spindle
Anaphase
Centromeres split
Sister Chromatids split<—now individual chromosomes
Anaphase-apart
Telophase
Final phase
Two daughter cells formed
Cleavage then new cells for animals
Cell plate which divide for plants
The Fluid Mosaic Model
Made of phospholipids, which can move
Bilayer is like a fluid
Phosphate group is hydrophylic
Contractile Vacuoles
Collects excess sater then expels it through the plasma membrane
prevents cells from bursting
Vacuoles
Sack of fluid surrounded by a membrane
TEMPORARILY stores food, enzymes, and wastes
Chloroplasts
Organelle that contains chlorophyll
Found in plants
Used for photosynthesis
Centrioles
Replicate in early interphase
Small, dark cylindrical structures
Made of microtubules, which help separate chromosomes during mitosis
Ribosomes
Found in pro- and eu-
Not membrane-bound
Involved in protein synthesis
Enzymes are assembled at the ribosomes
Rough ER
Studded with ribosomes
Contains enzymes for lipid synthesis
Smooth ER
Have no ribosomes
Contain enzymes for lipid synthesis
Mitochondria
Food is broken down to release energy
Have cristae<–see flashcard
Cristae
In mitochondria
Have large surface area
Produce energy-storing molecules
Lysosomes
Membrane-bound
Contain enzymes
Enzymes digest food particulates, viruses, bacteria, worn out cell parts, and sometimes the cell itself
AKA suicide sacs
Golgi Bodies
UPS of cell
receive, modify, and repackage proteins into forms the cell can use, expel, or store
Proteins are brought in and repackaged in new vesicles
Cytoplasm
Fluid, clear
Surrounding organelles and nucleus
Nucleus
control center of the cell
Has a nuclear membrane
Contains DNA<–guides all cell functions
Nucleolus
Produces ribosomes
Inside nucleus
RNA?
Cytoskeleton
Thin, fibrous elements
Provide support for organelles
Important for movement
Cell Wall
Plants only!
Firm, but flexible
Support + protection
Cilia
Short, numerous hair-like projections from the cell membrane
Movement
Flagella
Made of microtubules Long, threadlike Whip-like motion propels Only one or two Located on prokaryotes
