ap exam big idea: biological systems Flashcards
Organic compounds
Any compounds with carbon
chemical components of living matter
Nitrogen, carbine, hydrogen, oxygen, phosphorus, sulfur
hydrophillic
Compounds that easily dissolve In water, “water loving”q
hydrophobic
Compounds that do not dissolve in water
hydrolisis
Decomposition of something in the presence of water
NaCl(s)-> Na+ (aq) + Cl- (aq)
Dehydration synthesus
Opposite reaction of hydrolysis, ut releases water molecules and the difference in charge holds atoms together
Oxidation reduction reactions
Gain or loss of electrons - MECHANISM FOR ENERGY TRANSFER IN BIOLOGY
anabolism
Building complex materials out of simple substances
catabolism
Breaking down complex materials into simple substances (like oxidation)
exergonic reactions
release energy
endergonic reactions
Use up energy
Capillary action
Driven by the polarity of water - water will climb up a tube or move through spaces of material until gravity defeats it. Helpful in allowing water to go up roots
Amino groups
Forms peptide bonds between amino acids
carbonyl
Highly reactive carbonyl groups, highly reactive carbon near carbonyl group, INTERMEDIARY INREACTIONS
Carboxyl group
Weak acids that can donate a H+ ion to different reactions
hydroxyl group
Makes compounds soluble in water
Phosphate group
Stores and transfers energy
sulfhyrdryl
Stabilizes protein structure
prokaryotes
Plasma membrane, cell wall, cytoplasm, DNA, ribosomes, microtubules, often have flagella
eukaryotes
contain membrane bound organelles
nucleus
Contains DNA in form of chromosomes, selective protein permeable membrane,
endoplasmic reticulum
Rough er (has ribosomes on the outside): protein syntheis Smooth ER: lipid synthesis and detoxification
peroxisomes
Catalyze reactions that produce and degrade peroxide. Break fats into smaller molecules and help detoxify compounds in liver
mitochondria
Powerhouse of the cell - location of cellular respiration
grana
Stacks of thylakoids, membrain sacks inside the chloroplats
stroma
Fluid that surrounds gran inside the chloroplasts
Membranes
Composed mostly of lipids so they are hydrophobic, usually have a hydrophilic phospholipids on one end which goes on the center of the membrane (phospholipid bilayer).
Membranes have proteins, carbohydrate and sterols in them.
Protein functions in membranes
Transport molecules, receptor sites, surface enzymes, cell recognition, cell adhesion, cell, signaling
carbohydrate functions in membranes
Cell recognition and immune response
Cholesterol function in membranes
Control fluidity of membranes
Active transport
Forcing molecules to move against the concentration gradient - REQUIRES USE OF ATP
Facilitated diffusion
Diffusion through carrier proteins - DOES NOT require energy
glycocalyx
Protein and carbohydrate rich coating on call surface
hypertonic
High in solute, cells lose
hypotonic
Low in solute, cells take on water
Isotonic
Identical solute concentration
Electrochemical gradient
Determines what moves in and out of membranes when passive transport channels are open
Na+-K+ ATPase Pumpse
Example of active transport, the pump uses ATP to pull 2 k+ potassium ions into a cell and send 3 Na+ sodium ions out. (Called antiport) inside of the cell remains NEGATIVE because it pumps out three positives for every two it brings in
Ca++ ATPase pumps
Actively transport calcium from cytoplasm into ER. Sets up a strong calcium gradient that can be used for muscle contractions etc. ER muscle cells release the calcium when polarized by a nerve impulse, flooding the cytoplasm with Ca++ and causing contraction of cell (this is a uniport pump)
Water potential
Negative water potential demonstrates that the water is likely to diffuse from a place of high water potential to a place of low water potential
Photosynthesis reaction
6CO2 + 12H2O + light -> C6H12O6+ 6O2 + 6H2O
Photosynthesis light reaction basics
Light energy is harnessed to produce energy in the form of ATP and NADPH through photophosphorylation
MAKES ENERGY
Photosynthesis dark reaction (Calvin cycle)
Complete carbon fixation which uses CO2 from the environment and incorporates it into sugars using reduction of ATP and NADPH
MAKES SUGARS
c3 plants
Plants whose initial products of C fixation are two three carbon molecules synthesized using rubisco
c4 plants
CO2 is fixed into a four carbon molecule by the intermediate enzyme pyruvic acid and releases a CO2 molecule
Advantage in hot environments
CAM plants
Collect CO2 at night because its cooler outside
Example; cacti
Light reaction
Chlorophyll captures light energy to begin photosynthesis, light energy excites electrons which then jump to the reaction center where they move to the ETC to generate chemical energy as ATP or NADPH.
Cyclic photoposphorylation
Occurs in photosystem I to create ATP
Electrons move from reaction center through ETC back to the SAME reaction center.
Does NOT produce oxygen or NADPH
Non cyclic photoposphorylation
Starts in Photosystem II
Electrons move from reaction center to ETC and then MOVE to photosystem I. Lost electrons are replaced by breaking down water, which produces oxygen . the electrons that go to photosystem I are used to produce NADPH
ETC
As electrons go through the electron transport chain, protons are pumped out of the Strom into the thylakoid membranes creating a proton gradient. Protons flow through the Stroma into an ATP synthase to produce ATP which is then used in the Calvin cycle
Calvin cycle
NADPH provides the power to fix CO2 from the air into carbohydrates.
CO2 combines with RuBP sugar and is catalyzed to become a six carbon compound which is then split into two three carbon compounds. That compound is phosphorylated by ATP and reduced by NADPH to become PGAL, which can be used to synthesise glucose etc
Cellular respiration
- aerobic
- yields 36-38 ATP
- five stages: glycolysis, fermentation, pyruvate decarbocylation, citric acid cycle, ETC
fermentation
Anaerobic cellular respiration, glycolysis breaks down glucose 2ATP 2NAD+ into 2pyruvate 2ADP 4ATP 2H+ and 2H2O, pyruvate is converted to lactic acid or ethanol
step1: glycolysis
Oxidativee break down of glucose into two molecules of private, ATP and the reduction of NAD+ into NADH
2ATP used, 4 generated - net: 2
2NADH produced per glucose molecule
Glycolysis net reaction
Glucose + 2ADP + 2Pi + 2 NADP+ -> 2 private +2ATP + 2NADH + 2H+ +2H2O
step 2: pyruvate decarboxylation
Pyruvate is transported from cytoplasm into mitochondrial matrix where it loses a CO2 and the remaining acetyl group is transferred to coenzyme A to form Acetyl CoA
step 3: Citric Acid Cycle (Krebs cycle)
Begins when two molecules of acetyl CoA combine with oxaloaxetate to form citrate, after many reactions 2 CO2 are released and oxaloaxetate is regenerated and enters back into the cycle
Through this process, 4CO2, 6NADH, 2FADH2, 2ATP 4H+ and 2CoA are released
Step 4: electron transport chain
Located in mitochondrial membrane.
Oxidative phosphorylation produces ATP when electrons are transferred from NADH and FADH2 to oxygen by carrier molecules. When electrons are transferred across carriers, free energy is released hitch is used to form ATP
Carriers are reduced when they accept electrons and oxidized when they pass them on to the next
o2 is the final electron acceptors and picks up hydrogen along with electrons to form water
cyandide
Poison which blocks transfer of electrons and prevents cellular respiration
chemiosmosis
Used by cells to generate ATP by moving H+ ions across a membrane down a concentration gradient
osmoregulation
matinence of water and solute balance (part of homeostasis)
Homeostasis organs
Kidneys, liver, large intestine, skin
thermoregulation
Epinephrine : released by adrenal glands to increase metabolic rate and raise temperature
Positive feedback
Positive feedback mechanisms increase the output of a stimulus that has already been activated - considered unstable because they can lose control of the cycle
Negative feedback
As more feedback is received, it causes the process to change in the opposite direction. Allows stability by reducing fluctuations
Ex: sweat in humans
Nonspecific immune system
Fights off disease in general, not specific pathogens
Includes skin and mucus membranes
Mucus membranes have lysosomes that destroy bacterial cell walls
Specific immune system
Attacks very specific diseases using protein to protein interaction and is responsible for immunity to certain infections
macrophages
White blood cells that are part of the nonspecific immune system, they engulf foreign material (phagocytosis)
histamines
Released by basophils and mast cells, they cause capillaries to become “leaky” so that macrophages ad neutrophils can more easily reach the site of infection
lymphocytes
Major specific immune system defense
b cells or t cells
t cells
BASIC: THEIR JOB IS TO KILL PATHOGENS
Helper t: mediators between b cells and macrophages
cytotoxic: defense against viruses
Suppressor: control the immune response so it doesn’t grow out of control
b cells
BASIC: THEIR JOB IS TO SECRETE ANTIBODIES
Trained to have receptors that recognize specific set of foreign antigens - almost every one is capable of responding to a slightly different antigen
They become activated if tey come into contact with the cells that it have the antigen that goes with the antibody they carry
paratope
Where antibodies can bind to foreign proteins
neutrilization
When antibodies like antigen molecules, causing them to get stuck together and clump large amount of pathogens
precipitation
Antibodies bind to antigens aNd rapidly destroys them using phageocytosis
Lag period
Period in after exposure to pathogens, but before enough antibodies have been secreted
Memory cells
Antigen specific cells that remain after a primary infection
PH scale
Each step on PH scale represents a 10 fold addition of H+ ions
Free energy change
If the free energy change is greater than zero the reaction is non spontaneous
If the free energy change is less than zero the reaction is spontaneous
If its zero, it is at equilibrium
peroxisomes
contain oxidative enzymes to break down fats and detoxify harmful chemicals
ATPase
Enzymes that turn ATP into ADP and drive chemical ion pumps that maintain ion concentration across cell membrane
Limiting factors of the dark reaction
Temperature, light, carbon dioxide
stomata
regulate the entrance of CO2 into a plamt
Oxidative phosphorylation
Takes place across the inner mitochondrial membrane
