AP Bio - Unit 2: Cells

Light Microscope

Light Microscope

Type of microscope with the least magnification and lowest resolution (2000x)

TEM

Type of microscope that kills the organism, can magnify 200,000x, excellent resolution, can see the inside of a cell

SEM

Type of microscope that can magnify 2,000,000x and can see the outside of a cell

Prokaryotes

Bacteria, 10-100x smaller than eukaryotic cells, single-celled organisms, only have ribosomes and one DNA loop

Eukaryotes

Anything other than bacteria, 10-100x bigger than prokaryotic cells, has many organelles

Plasma Membrane

1. All cells

2. Phospholipid bilayer with proteins embedded throughout

3. Cover and protect the cell, control what goes in and out

Cytoplasm (aka Cytosol)

1. All cells

2. Mostly water with some dissolved solutes

3. Gives cell shape, most chemical reactions occur here

Nucleus

1. Only eukaryotes

2. Double nuclear membrane/envelope with nuclear pores, nucleoplasm, the nucleoli to make ribosomes, chromatin DNA

3. Protect genetic code, regulate most cell activity

Ribosomes

1. All cells

2. Large and small ribosomal subunits full of rRNA and proteins

3. Make proteins

Smooth Endoplasmic Reticulum

1. All eukaryotes

2. 100% membrane, cisternae on the outside, lumen on the inside

3. Transportation within the cell, makes more plasma membrane, makes most membrane-bound organelles, makes lipids

Rough Endoplasmic Reticulum

1. All eukaryotes

2. 100% membrane, cisternae on the outside, lumen on the inside, bound ribosomes on the outside

3. Transportation within the cell, makes proteins that export the cell

Golgi Apparatus

1. Only eukaryotes

2. 6-8 stacked membranes with cisternae on the outside and lumen on the inside, vesicles on the bottom, made by recycled smooth ER

3. Modify, edit, and package proteins

Vacuoles and vesicles

1. All eukaryotes

2. Membrane Sacs

3. Storage

Lysosomes

1. Animal cells

2. Vacuole with strong digestive enzymes

3. Digest starches, carbs, organelles, cells

Peroxisomes

1. Eukaryotic Cells

2. Vacuole with strong digestive enzymes

3. Digest adenine, guanine, hydrogen peroxide, and toxins

Mitochondria

1. All eukaryotes

2. Two membranes, inner membrane has cristae folds to create a matrix, contains ribosomes and a loop of DNA, intermembrane space between the membranes

3. Cellular respiration

Chloroplasts

1. Plants and algae

2. 2 smooth outer membranes, thylakoid membrane (chlorophyll), stroma (individual), granum (stacks), ribosomes, DNA loop

3. Photosynthesis

Endosymbiotic Theory

Mitochondria and Chloroplasts were once prokaryote cells that got eaten by a larger eukaryote cell through phagocytosis

Microtubules

1. All eukaryotes

2. Proteins only, no membranes, made of tubulin proteins, make up cilia and flagella, 25nm in diameter

3. Cell division

Microfilaments

1. All eukaryotes

2. Actin proteins, 7 nm in diameter, found in microvilli

3. Cell division and muscle contraction

Intermediate Filaments

1. All eukaryotes

2. Made of keratin proteins, 8-12 nm in diameter

3. Structural support

Centrosome

1. Animal cells

2. Centrioles of perpendicular 9+0 microtubules

3. Cell division

Cilia and Flagella

1. Prokaryotes and Eukaryotes

2. 9+0 base, 9+2 center, dynein arms (proteins)

3. Cell movement

Cell Walls

1. All but animal cells

2. Middle Lamella, Primary __ __, Secondary __ __, Plasma Membrane for communication, plasmodesmata in between segments

3. Structure, protection

Bacteria Cell Walls

Made of peptidoglycans

Fungal Cell Walls

Made of chitin

Extracellular Matrix of Animal Cells

Structure: Collagen and fibronectin with proteoglycan complexes above a plasma membrane

Gap Junctions

Space between animal cells for communication

Desmosomes

To stick animal cells together with long strands of keratin

Tight Junctions

Proteins woven together to help tighten the animal cell membrane, preventing rupture and leakage

Tertiary

Protein folding level in the cell wall

Amphipathic

Polar and nonpolar (cell walls)

Lateral Movement

Sideways movement of phospholipids in the cell wall; ~10^7 times per second

Flip-Flop

Up and down movement of phospholipids in the cell wall; once a month

Unsaturated

Fluid fatty acids

Saturated

Viscous fatty acids

Passive transport

Osmosis and diffusion

Turgid

Plant cell in a hypotonic environment

Lyse

Animal cell in a hypotonic environment

Plasmolysis

Plant cell in a hypertonic environment

Shrivels

Animal cell in a hypertonic environment

Flaccid

Plant cell in an isotonic environment

Cotransport System

Active and passive together through separate proteins

Root hairs

What water diffuses into for diffusion in plant roots

Active Transport

What minerals go through in transportation in plant roots

Water

What xylem cells conduct

Sugars

What phloem cells conduct

Capillary Level

What level diffusion occurs at