1spontaneous generation
nonliving materials can give rise to living organisms
. excludes viruses
2unified cell theory
all life is made from cells + all cells come from other cells
3Constraints on cell size
1. Use Dna as their genetic material
2. plasma/cell membrane is made of phospholipids
3. Use ribosomes to make proteins
4Prokaryotes
no nucleus + no membrane-bound organelles
5Nucleoid
"false nucleus", where DNA is located
6Cell wall
support/structure/protection
7Capsule
sticky layer of carbohydrates or proteins - adhere to surfaces
8Flagellum
used for movement
9Diversity of prokaryotes
1. Domain bacteria - found in all environments that support life
2. Domain archaea - "extremophiles"
10eukaryotes
nucleus + organelles
11Nucleus
double membrane, contains dna
12Chromatin
uncoiledncondensed form of dna
13Chromosomes
coiled/condensed form of dna, present only during cell division
14Nucleolus
site of RNA synthesis
15Mitochondria
creates ATP (usable form of energy) by cellular respiration
Double membrane, outer membrane, inner membrane with extensive folds called cristae (increases surface area), filled with liquid called the matrix
16Peroxisomes
break down fatty acids — produces H2O2 (hydrogen peroxide) as a byproduct — recycles H2O2 into H2O + O2 (oxygen)
17features shared by ALL cells
1. Use Dna as their genetic material
2. plasma/cell membrane is made of phospholipids
3. Use ribosomes to make proteins
18Vesicles
used for transport - generally smaller
19Vacuoles
used for storage - generally larger
20The endomembrane system
connected physically or by moving things back and forth with vesicles
21Endoplasmic reticulum (ER)
network of flattened sacs + tubules
22Rough ER
studded with ribosomes (Ribosomes make protein) - processes proteins
23Smooth ER
lacks the attached ribosomes, processes other molecules, stores calcium ions, detoxifies poisons (does multiple functions)
24Golgi Apparatus
cells shipping + processing station
25Lysosomes
filled with hydrolytic enzymes — digestion
26Animal cells
Generally small
Centrosomes - microtubule organizing region (cell division)
Lysosomes - used for digestion
No cell wall
Mitochondria ( use ATP to create energy)
27Plant cells
100-1000x larger than animal cells
No centrosomes
No lysosomes
Cellulose (polysaccharide) cell wall
Chloroplasts (Photosynthesis) + mitochondria
Central vacuole - takes up to 99% of internal volume in a plant cell (storage of water, pigments, poisons)
28Cytoskeleton
"cell skeleton" - structures, support, movement
Smallest - Microfilaments
To - Intermediate filaments
Largest - microtubules
29Connections between cells
how cells form tissues
30Two ways tissues are formed
Extracellular matrix - dense external network of proteins
Intercellular junctions
31Plasmodesmata
small holes through the cell wall — connect adjacent plant cells (only found in plants and not animals)
32Tight junctions
form watertight barriers (Found in animals not plants)
33Desmosomes
allow tissues to repeatedly stretch and return to their original shape (Lungs, bladder, heart etc) (Only found in animals and not plants)
34Gap junctions
small holes connecting adjacent animal cells (Only found in animals not plants)