test 1 Flashcards
Fracastoro
Italian physician; 1546- (pathogenic theory of medicine) epidemic diseases caused by transferable tiny particles or spores that could transmit infection by direct/indirect contact over a long distance; entities that could not be seen with the naked eye
bassi
the germ theory, replaced Fracastoro’s theory(pathogenic theory of medicine) proposes that microorganisms are the cause of many diseases later validated in late 19th century
Zacharias jansen
ditch spectacle maker invented the first microscope; first true compound microscope in 1595
antonie van leeuwenhoek
father of the microscope; first described microscopic organisms using the scope; father of microbiology; first to observe and describe single cell organisms(animolecules); first to observe microscopic of muscle fibers, bacteria, sperm and even blood flow of capillaries
postulates of the cell theory
- all living organisms are composed of one or more cells
- cells are the basic functional unit of all living organisms
- all cells arise from pre-existing cells
Theodore schwan
1830s reported the presence of cells in animal tissue
matia schliden
also described the presence of cells in plants
Rudolph ruchild
extended the cell theory and concluded that all cells arise form pre-existing cells
cytology
study of cells; cells can be viewed by a microscope; use of the microscope is microscopy; cell is measured in micrometers; 1,000,000 micrometers in 1 meter
comparison of cells
flat, cylindrical, oval and irregular in shape; smallest to largest( virus, blood cell, plant cell, human egg)
light microscopy(LM)
uses visible light that passes through the cell
transmission electron microscopy
uses a beam of electrons that passes through the cell; can magnify about 100x greater than LM; most useful in visualizing small viruses
scanning electron microscopy
uses a beam of electrons which is reflected off the surface of a cell to provide a 3D study of the cell surface
four essential categories of biological molecules
proteins, carbohydrates, lipids, nucleic acids
macromolecules
proteins, nucleic acids, and carbs can exist as chains called polymers; polymers are composed of smaller subunits called monomers; monomers are amino acids, nucleotides, and monosaccharides
what do proteins do in the cell
essential parts of organisms and participate in virtually every process within cells; many are enzymes; structural or mechanical functions; important in cell signaling, immune responses, cell adhesion and the cell cycle; vital to cellular metabolism; acts in myosin; necessary in animal’s diets
protein
macromolecules composed of combinations of 20 different types of amino acids bound together with peptide bonds
amino acids
nh2-amino
cooh-carboxyl
r group changes in each amino acid
used to build proteins
peptide bond formation
dehydration synthesis reaction
primary protein structure
amino acid sequence
secondary protein structure
local sub structure (alpha helix, beta sheets) defined by hydrogen bond
tertiary protein structure
3d structure, alpha helix and beta sheet start folding into compact shape
quaternary protein structure
stabilized
what do carbohydrates do
polysaccharides serve for the storage of energy and structural components; monosaccharide ribose is an important component of the genetic molecule RNA; saccharides play key role in immune system, fertilization, blood clotting and development
carbohydrate configurations
monosaccharide (glucose), disaccharide (sucrose), and polysaccharide (cellulose)
pancreatic cells
make insulin and use amino acids in order to synthesize insulin by the process of dehydration synthesis
nucleic acids
DNA and RNA
nucleotides
phosphate group
sugar backbone
base
needed to synthesize a new strand of DNA
DNA
double helix; thymine as fourth base; sugar deoxyribose
RNA
single strand; uracil as the 4th base; sugar ribose
lipids
broad group of molecules- fats, waxes, steroids, fat soluble vitamins(A, D, E, and K), monoglycerides, diglycerides, phospholipids
functions: energy storage, structural component of cell membranes, important signaling molecule
no polymers; all are insoluble in water
simple lipids
contain only C, H, O (fatty acids and triglycerides)
compound lipids
contain elements in addition to C, H, O (phospholipids, steroids)
lipids are important to
biological systems b/c some lipids are potentially large sources of energy to perform cellular work
fatty acids
can be saturated or unsaturated
triglycerides
composed of three fatty acids bonded to a glycerol molecule
saturated fatty acids
solid fat
unsaturated fatty acids
liquid fat
phospholipid structure
hydrophobic tails; hydrophilic heads; choline-phosphate-glycerol-fatty acids
steroids
molecules with four interlocking hydrocarbon rings
cell membrane
allows small molecules to pass freely, large particles regulated by transport proteins
cytoskeleton
transportation, gives shape and helps organize the events of cell division; comprised of protein subunits organized throughout the cytosol; microfilaments, intermediate filaments, microtubules
mitochondrion
generates cell’s energy; own independent genome. own proteins to participate in a variety of cellular activity; bean shaped, double membrane; produce ATP using ETC
nucleus
safely store DNA, separates cell DNA from activity og cytoplasm; proteins work together to copy segments of DNA into RNA in a process called transciption
endoplasmic reticulum
surrounds nucleus, chemical reactions, store enzymes in SER, fresh proteins are packed into vesicles and sent to Golgi apparatus; ribosomes attach to RER, read RNA and translate into proteins; network of intracellular membrane bound tunnels
Golgi apparatus
molecules are tagged with specific labels that transport proteins; receive proteins and lipids from the RER and modify, sort and package- post office of cell
lysosome
deals with transported proteins; vesicles generated by the Golgi apparatus; contain enzymes used to digest and remove waste products and damaged organelles within the cell (autophagy); when a cell is dying it releases lysosomal enzymes that digest the cell (autolysis)
vacuole
store nutrients, break down waste, help cell grow, provide pressure to maintain plants shape
chloroplast
convert CO2 and H2O into sugar (photosynthesis) own independent genome
cell wall
protects and provides skeletal support
prokaryote cells
single, tiny, no organelles, circular DNA (bacteria); lack a membrane bound nucleus and other membranes organelles
eukaryote cells
single or multi, relatively large, with organelles, chromosome DNA (protists, fungi); have a membrane bound nucleus that contains the genetic material
functions of cells
covering, lining (epithelial cell); storage (hepatocytes, adipocytes); movement (muscle cell); connection (multiple cell types); defense (lymphocytes); communication (neurons); reproduction (sperm, oocytes)
cellular components
almost all cells in the body have three basic regions or components: plasma (cell) membrane, cytoplasm, nucleus
plasma (cell) membrane
forms an extremely thin outer border of each cell; gatekeeper; out membrane
composition and structure of membranes
many membranes within the cell; all membranes have similar structure and composition; membranes consist of the components: lipids and proteins
membrane lipids
two layers outer and inner; insoluble in water; three types: phospholipids, cholesterol, glycolipids
phospholipids
majority of lipids; polar (charged) and non polar (uncharged) region; when exposed to water always form a phospholipid bilayer
cholesterol and glycolipids
cholesterol strengthens and stabilizes membrane against extreme temperature; 20% of all lipids
glycolipids are lipids with carb molecules attached; 5-10% of lipids
membrane proteins
proteins give selective permeability; complex, comprised of chains of amino acids; integral or peripheral
integral membrane proteins
embedded within the phospholipid bilayer; span the entire thickness of membrane; transmembrane proteins; exposed to the outside and inside of cell; carbs can be attached to outer surface (glycoproteins)
peripheral proteins
loosely attached to the external or internal surface of the plasma membrane
functions of plasma membrane
communication’ intercellular connection; physical barrier; selective permeability
cytoplasm
includes: cytosol, organelles, inclusions
cytosol
watery; a viscous, syruplike fluid containing many different dissolved substances such as ions, nutrients, proteins, carbs, amino acids
organelles
little organs; membrane bound or non-membrane bound
membrane bound organelles
phospholipid bilayer; membrane separates contents of organelles from cytosol
smooth ER
continuous with RER; synthesis, transport, and storage of lipids including steroid hormones; metabolism of carbs; detox of drugs, alcohol and poisons; lysosomes
rough ER
attachment of ribosomes; synthesize, transport and store proteins destined to be: secreted by the cell, incorporated into the plasma membrane, enclosed with lysosome; involved in the production of proteins that are exported from the cell
non membrane bound organelles
ribosomes cytoskeleton centrosomes and centrioles cilia and flagella microvilli
ribosomes
comprised of a small and large subunit; responsible for all protein synthesis within the cell; free ribosome float within the cytosol; fixed ribosomes attached to the outer surface of membranes associated with RER; quaternary protein structure
microfilaments
maintain and change cell shape; participate in muscle contraction and cell division
intermediate filaments
provide structural support and stabilize junctions between apposed cells
microtubules
radiate from centrosome, fix organelles in place, maintain cell shape and rigidity; direct movement of organelles inside the cell; facilitate cell motility of cilia and flagella
centrosome and centrioles
centrosome- consists of a pair of centrioles at right angles to each other
centriole- consists of nine sets of three closely aligned microtubules; cell division
cilia and flagella
projections extending from the cell; both are capable of movement
cilia- found on cells whose function is to move objects across the surface of those cells of the respiratory tree and oviduct
flagella- longer and usually appear alone, help to propel a cell
living cell
miniature factory where thousands of reactions occur; converts energy in many ways organism’s metabolism transform matter and energy. subject to the laws of thermodynamics
metabolism
totality of an organism’s chemical reactions; arises from interactions between molecules; 1000s of reactions every second; complex
catabolic pathways
break down complex molecules into simpler compunds; release energy; drive the regeneration of ATP from ADP and phosphate
metabolic pathways
many steps; begin with a specific molecule and end with a product; that are each catalyzed by a specific enzyme
anabolic pathways
build complicated molecules from simpler ones; consume energy
energy
capacity to cause change (work); exists in various forms, of which some can perform work; can be converted from one form to another; released from ATP when terminal phosphate bond is broken
ATP hydrolysis
can be coupled to other reactions; endergonic (unfavorable, not spontaneous); exergonic (spontaneous); coupled (spontaneous)
kinetic energy
motion;
potential energy
location of matter; includes chemical energy stored in molecular structure; stored in bonds
enzymes
proteins (long molecules that are folded into a specific shape; catalase, amylase, pepsin, trypsin; biological catalysts; occur inside cells or are secreted by the cells; can be re-used; produces product molecule
catalysts
substance that speeds up the rate of a chemical reaction but is not itself changed by the reaction
active site
the site on the enzyme where the reaction occurs
substrate molecules
molecule the enzyme acts on
lock and key hypothesis
states that the active site specifically matches the shape of the substrate molecule
temperature
effects rate of enzyme; low temps cause slow enzymes; high temps increase reactions, bind quicker, only occurs up to the optimum temp of 40C; after the optimum temp the enzyme denatures ( enzyme changes shape, active site no longer matches the shape of the substrate molecule)
controlled variable
volume and concentration of substrate, volume and concentration of enzyme ph, temperature
cellular metabolism
breathing and cellular respiration are related
glycolysis
the cytosol of the cell; breaks down glucose to pyruvic acid; generally the mose readily available substance derived from food or glycogen; can occur without oxygen
transition reaction
each pyruvic acid molecule is broken down to form co2 and a two carbon acetyl group
Krebs cycle
in the mitochondrial matrix; uses acetyl co-a to generate ATP, NADH, FADH2, and CO2
electron transport chain
along the inner mitochondrial membrane; allows H atoms to flow, higher concentration outside of the cell; like a dam; chemiosmosis produces up to 38 ATP molecules
fermentation
requires NADH generated by glycolysis; takes place in cytosol; yeast produce carbon dioxide and ethanol; muscle cells produce lactic acid; only a few ATP are produced per glucose
