Chapter 6
1000 um =1 mm
Nanometers are used for: organelles
Prokaryotic- bacteria (smaller) ex: salmanilla
Eukaryotic- animal
3 Domains: Archaea, Bacteria, Eukarya
Archaea- extremophiles; very high pH, very low pH, very high/low temperatures
Bacteria- single cell prokaryotes, moderate climate (average)
Eukarya- 4 groups; Protists (amiba), Fungi (can be multi or uni cellular (absorbs nutrients) ex: mushrooms, yeast
Basic features of all cells: Plasma membrane (cell membrane/phospholipid bilayer), Cytosol/Cytoplasm, Chromosomes (carry genes)/DNA, Ribosomes (make proteins, measured in nm)
Prokaryotic Cells: no nucleus, DNA in an unbound region, no membrane bound organelles (only organelle is ribosomes), Cytoplasm (bound by the plasma membrane; EVERYTHING inside)
Eukaryotic Cells: DNA, nucleus, membrane bound organelles, both plant and animal cells, cytoplasm, and plasma membrane
Cytoplasm- region between the plasma membrane and nucleus
Plasma Membrane- barrier, semi-permiable (allows oxygen + nutrients in, and pushes waste out of cells
Diffusion- can occur better through smaller cells (prokaryotic?)
Nucleus (headquarters)- contains most of the DNA and genes (chromosomes)
Ribosome (factory)- makes proteins (from DNA)
Humans have how many pairs of genes? Answer- 23
Ribosomes are: attached to the outside of the molecule, attached to the rough ER, and and free floating “Bound” and “Free” ribosomes.
Chromatin- DNA wrapped around proteins
Pores- regulate the entry and exit of molecules from the nucleus
Chromosomes: tightly wound; for the 10% of the time when Mitosis occurs (the DNA bonds together to form X chromosomes)
Chromatin: loose, stretched; 90% of the time, when DNA is at rest
Nucleolus- located within the nucleus and makes RNA
rRNA- ribosomal RNA
mRNA- messenger RNA
Endomembrance System- Nuclear envelope, Endoplasmic Reticulum (smooth and rough ER), Golgi Apparatus, Lysosomes, Vacuoles, Plasma Membrane, Vesicles (connects these components via transfer)
The tubules and sacs are all thought to interconnect, so that the ER membrane forms a continuous sheet enclosing a single internal space. This highly convoluted space is called the: ER lumen or the ER cisternal space, and it often occupies more than 10% of the total cell volume.
More membrane= more metabolic reactions/ use of enzymes
Endoplasmic Reticulum (ER): accounts for more than half of the total membrane in many eukaryotic cells
Smooth ER- lacks ribosomes
Rough ER- surface studded with ribosomes
Rough ER functions: (glycoprotein= sugar+protein) Transport Vesicles separate proteins surrounded by membranes; Membrane factory for the cell
Smooth ER functions: Synthesizes lipids(ovaries and testes), Metabolizes carbohydrates, Detoxifies drugs and poisons(liver), and stores calcium ions(muscles)
Fatty Acids- inglycerol, triglycerol, steroids, and phospholipids
Golgi Apparatus(post office of the cell)- consists of flattened membranous sacs called cisternae
Vesicles are always going in and out of the: golgi
Functions of the Golgi: modifies products of the ER, manufactures certain macromolecules, and sorts and packages materials into transport vesicles
Lysosomes(garbage disposal of the cell)- spheared pouch (membrane bound), membranous sac of hydrolytic enzymes that can digest macromolecules (low pH and high H concentration)
Phagocytosis- lysosome digesting food
Autophagy- (self eating/breaking down damaged organelles) lysosome breaking down damaged organelles
Vacuoles- large vesicles derived from the ER and Golgi
Food Vacuoles- formed by phagocytosis(animal cells)
Centractile Vacuoles- pump water out of cells(protists)
Central Vacuoles- plants cells, hold water(large central vacuoles)
Protists- normally in pond water, uni cellular; paramecium
Endomembrane System: trying to move things form one place to another
Mitochondria- where ATP is made; large surface area for sythesizing ATP Cristae (the protrusions)
Chloroplast- captures light energy for photosynthesis (plants and algae)
Stroma- liquidy interior
Chloroplasts- type of plastid