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4 levels of protein structure
primary structure
secondary structure
tertiary structure
quaternary structure
primary structure
linked series of amino acids with a unique sequence
secondary structure
polypeptides repeatedly folded and coiled
tertiary structure
overall shape of polypeptide resulting from interactions between the side chains of the various amino acids.
quaternary structure
overall protein structure that results from the aggregation on these polypeptide subunits
dehydration synthesis
The chemical process by which a molecule of water is removed from the reactants to join the reactants together.
Hydrolysis is a chemical process in which a molecule of a target substance is split into two parts by the addition of a molecule of water
motility structure present in some animal cells, composed of microtubules within an extension of the plasma membrane
endoplasmic reticulum
network of membraneous sacs and tubes, active in membrane synthesis and other synthetic and metabolic processed.. has rough ribosome studded and smooth regions
region where the cells microtubules are initiated , contains pair of centrioles.
reinforces cell shape , functions in cell movement , components made of proteings includes microfilaments, intermediate filaments, and microtubules.
organelle where cellular respiration occurs and most ATP is generated.. change energy to a form cells can use.
main brain of the cell
complexes that make proteins, free in cytosol or bound to rough ER or nuclear envelope.
golgi apparatus
active in synthesis , modification and sorting and secretion of cell products
produces hydrogen peroxide as a by product then converts to water
storage and breakdown of waste products , hydrolysis of macromolecules .
photosynthetic organele, converts energy of sunlight to chemical energy stored in sugar molecules.change energy to a form cells can use.
connect the cytoplasm for adjacent walls
cell wall
outer layer that maintains cells shape and protects form mechanical damage.
How are plant and animal cells different?
plant cells have a cell wall that made up of cellulose
eukaryotic cell
contains a nucleus
prokaryotic cell
no nucleus
speeds up a reaction without being consumed by a reaction
enzyme inhibitors
a molecule that binds to enzymes and decreases their activity
2 laws of thermodynamics
1st: energy in the universe is constant
2nd: energy conversions increase the disorder of universe
cellular respiration
bodes way of breaking down food molecules and making their strored energy available to the cell.
hydrogen acceptor
Any substance that is capable of becoming reduced and accepting hydrogen atoms, which allows the release of energy from such a reaction.
redox reaction
Oxidation is the loss of electrons or an increase in oxidation state by a molecule, atom, or ion.
Reduction is the gain of electrons or a decrease in oxidation state by a molecule, atom, or ion.
how do autotrophs, heterotrophs and decomposers interact
Autotrophs (producers) are usually plants and synthesize their food with the help of sunlight. Heterotrophs are the organisms that feed on these plants(herbivores), or on the animals that are feeding on these plants(carnivores). these are collectively called as consumers. when all these producers and consumers die, the organic matter in their bodies are fed upon and thus broken down by decomposers. these thus release complex matter to simple forms which are again ready to be taken up by the plants. the cycle continues.
photosystem 1
is the second photosystem in the photosynthetic light reactions of algae, plants, and some bacteria.
photosystem 2
first protein complex in the Light-dependent reactions. It is located in the thylakoid membrane of plants, algae, and cyanobacteria. The enzyme uses photons of light to energize electrons that are then transferred through a variety of coenzymes and cofactors to reduce plastoquinone to plastoquinol. The energized electrons are replaced by oxidizing water to form hydrogen ions and molecular oxygen. By obtaining these electrons from water, photosystem II provides the electrons for all of photosynthesis to occur.
where does photosynthesis occur
Photosynthesis occurs in the chloroplasts (which contains the pigment Chlorophyll) of plant cells.
cyclic photoshphosphoryliation
produces energy needed for the reaction
non cyclic photoshphosphoryliation
produces NADPH and ATP for the dark reaction
internal system of chloroplast
The material within the chloroplast is called the stroma, corresponding to the cytosol of the original bacterium, and contains one or more molecules of small circular DNA. It also contains ribosomes; however most of its proteins are encoded by genes contained in the host cell nucleus, with the protein products transported to the chloroplast.

TEM image of a chloroplast
Within the stroma are stacks of thylakoids, the sub-organelles, which are the site of photosynthesis
light reaction
occurs in the sunlight
dark reaction
goes through a cycle and forms glucose with NADP+ and ADP being recycled back to a light reaction
enzymes,structure, receptors , transport
nucleic acid
information storage and transfer
how does flagella work
Flagella is a single tail, which is made from myosin and actin filaments, call it one mini muscle, that pushes the cell in one direction. A perfect example of this is Human sperm.
hey work to make reactions go faster in digestive and metabolic (energy related) processes. They are called 'catalysts' because they speed up the reaction by lowering the amount of energy needed to get the reaction started.
a chemical reaction which invloves breaking down complex molecules to simple substances.
reaction that breaks macromolecules into constituent individual subunits
It's a chemical reaction in which the standard change in free energy is positive.
Exergonic reactions are chemical reactions in which energy is released as heat.
how does light interact with the pigments in photosynthesis
Because they interact with light to absorb only certain wavelengths, pigments are useful to plants and other autotrophs --organisms which make their own food using photosynthesis. In plants, algae, and cyanobacteria, pigments are the means by which the energy of sunlight is captured for photosynthesis.