Cells Flashcards
History
(1665) first microscope
(1838) in animals
Cells
Smallest unit of life
60-100 trillion in human body, over 200 diff types
Cell theory
1) cells are the fundamental unit of life
2) all organisms are composed of cells
3) cells arise only from other cells
Plasma membrane (cell membrane)
Outside
Cytosol (cytoplasm)
Gelatinous fluid
Organelles
“Little organs” inside cell
Cilia
Multiple short hair-like
Flagellum
Usually 1 or 2, long hair-like
Nucleus
Control center
Nuclear envelope (nuclear membrane)
Double membrane w/many pores
Nucleoplasm
Like cytosol
Nucleolus
Produces ribosomes
Chromosomes
Genetic organelles
Total of 46 in most human cells
Mitochondria
Release energy
Ribosomes
Produces proteins
Eg: looks like jellybeans
Endoplasmic reticulum
Circulation
Rough endoplasmic reticulum
Covered with ribosomes
Smooth endoplasmic reticulum
Lack ribosomes
Golgi complex (Golgi body)
Packages chemicals
Vesicles
Membrane bound packets of chemicals
Vacuoles
Store water, huge in plants
Lysosomes
Store digestive chemicals
Centrioles (centromere)
Animal cells ONLY
Pair organizes cell division
Cytoskeleton
Proteins in cytosol
Microtubules
Hollow proteins
Microfilaments
Solid proteins
Monera
- Prokaryotic
- Uni Cell
- Cell Wall (+)
- Chloroplasts (-)
- Centrioles (-)
Protista
- Eukaryotic
- Uni Cell
- Cell Wall (+/-)
- Chloroplasts (+/-)
- Centrioles (+/-)
Plantae
- Eukaryotic
- Multi Cell
- Cell Wall (+)
- Chloroplasts (+)
- Centrioles (-)
Fungus
- Eukaryotic
- Multi Cell
- Cell Wall (+)
- Chloroplasts (-)
- Centrioles (-)
Animalia
- Eukaryotic
- Multi Cell
- Cell Wall (-)
- Chloroplasts (-)
- Centrioles (+)
Cell wall
Rigid layer outside plasma membrane
Cellulose binds adjoining cells
Central vacuole
Huge reservoir in plants (store water)
Plastids
Specialized vesicles, including chloroplasts
Store chlorophyll for photosynthesis
Eukaryotic cells (Kingdoms)
In Protista:
Plants, Fungi, Animals
Eukaryotic cells
Many membrane, bound organelles
Prokaryotic cells
In bacteria
100 times smaller, more primitive
No nucleus, few organelles, diff cell wall
Phospholipid bilayer
2 layers of lipids embedded w/ proteins Both surfaces (phosphate) are water-soluble, interior (fatty acids)
Plasma membrane
1 bilayer
Nuclear envelope
2 bolsters
Plasma membrane is selectively permeable (ability to go through)
Whether a substance can pass through depends on its size + solubility
Lipid
Soluble substances, dissolve through lipids
Water
Soluble substances, not permeable unless small enough to fit through protein pores.
Passive transport
Moves from HIGH => LOW concentration
(Automatic) does not require energy
Simple diffusion
Random movement
Facilitated diffusion
Uses carrier molecules
Active transport
From LOW => HIGH concentration, used carrier molecules + energy
Endocytosis
Swallowed by plasma membrane
Phagocytosis
Solids
Pinocytosis
Fluids
Exocytosis
Expels or secretes vesicle
Osmosis
Diffusion of water through membrane, when water either enters or exits cell
Isotonic solution
Same concentration outside as inside cell
Dynamic equilibrium, so no net change
Hypotonic solution
Less chemical than inside cell
More water outside cell
Water moves into cell to divide it, so cell gains water, swells or bursts
Hypertonic solution
More chemical than inside cell
Less water outside cell
Water leaves cell to concentrate it, so cell loses water + shrinks