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lipid

an organic compound used by cells as long-term energy stores or building blocks. they are hydrophobic and insoluble in water because they contain a hydrocarbon tail that is nonpolar and repellent to water

lipids

fats, oils, steroids, and phospholipids

fats

lipids made of glycerol and three fatty acids, used as long-term energy stores in cells. not as easily metabolized as carbohydrates, but are more effective at storage

saturated fat

fat that contains no double bonds, associated with heart disease and atherosclerosis, found mostly in animals

unsaturated fat

fat that has mono or poly double bonds, so it has less hydrogens per carbon, found mainly in plants

steroid

a lipid composed of four carbon rings

steroids

cholesterol, testosterone, progesterone, and estrogen

cholesterol

a steroid, an important structural component of cell membranes

phospholipid

a lipid formed by combining a glycerol molecule with two fatty acids and a phosphate group. they are bilateral structures with a hydrophobic tail (hydrocarbon chain) and a hydrophilic head (the phosphate group) the major component of cell membranes; the hydrophilic phosphate group is the outside and the hydrocarbon tail is the interior

carbohydrate

used by cells in energy-producing reactions and as structural materials. they have the elements C, H, and O, with H and O in a 2:1 ratio

carbohydrates

monosaccharides, disaccharides, and polysaccharides

monosaccharide

a simple sugar, and the simplest form of a carbohydrate. example: glucose, which is used in cellular respiration to provide energy for cells. these with five carbons are used in genetic molecules (RNA) and high-energy molecules (ATP)

disaccharide

a sugar consisting of two monosaccharides bound together. this includes sucrose, maltose, and lactose

sucrose

a major energy carbohydrate in plants; a combination of fructose and glucose

maltose

a carbohydrate used in the creation of beer, a combination of two glucose molecules

lactose

found in dairy products, a combination of galactose and glucose

polysaccaride

a carbohydrate containing three or more monosaccharide molecules. they act as a storage form of energy (starch and glycogen) and as structural material around cells (cellulose and chitin)

starch

a polysaccaride made solely of glucose molecules is the energy storage form of choice for plants

glycogen

a polysaccaride made of glucose, but stored energy in animals, found most often in liver and muscle cells

cellulose

a polysaccaride composed of many glucose molecules is used by plants in the formation of cell walls

chitin

a polysaccaride that is an important part of the exoskeletons of arthropods (insects, spiders, and shellfish)

protien

a compound composed of chains of amino acids. it has many functions, including serving as structural components, transport aids, enzymes, and cell signals to name only a few

amino acid

consists of a carbon center surrounded by an amino group, a carboxyl group, a hydrogen, and an R group

primary structure

the specific sequence of amino acids making up a polypeptide chain, the first level of protein structure

secondary structure

3-D arrangement of a protein caused by hydrogen bonding at regular intervals along the polypeptide backbone

tertiary structure

3-D arrangement of a protein caused by interaction among the various R groups of the amino acids involved

quaternary structure

the arrangement of separate polypeptide "subunits" into a single protein. not all proteins have this, many consist of a single polypeptide chain

fibrous proteins

proteins with only primary and secondary structures-but may contain a quaternary structure if there's more than one polypeptide chain

globular proteinss

proteins with only primary, secondary, and tertiary structures. may contain quaternary structure if there is more than one polypeptide chain

enzymes

proteins that act as organic catalysts. they speed up reactions by lowering the activation energy needed for the reaction to take place. they are selective, and interact with only particular substrates. their shapes provide this specificity

substrates

the substances that enzymes act upon

active site

the part of the enzyme that interacts with the substrate

induced-fit model

of enzyme-substrate interaction describes the active site of an enzyme as specific for a particular substrate that fits its shape. when the enzyme and substrate bind, the enzyme is induce to alter its shape for a tighter active site-substrate attachment. this tight fit places the substrate in a favorable position to react, accelerating the rate of reaction. after an interacts with a substrate, converting it into a product, it is free to find and react with another substrate, so you don't need a large concentration of enzyme to have a major effect on the reaction

these alter enzyme effectiveness

the temperature, pH, concentration of the substrate, and concentration of the enzyme

competitive inhibition

an inhibitor molecule resembling the substrate binds to the active site and physically blocks the substrate from attaching. may be overcome by adding a high concentration of substrate to outcompete the inhibitor

noncompetitive inhibition

an inhibitor molecule binds to a different part of an enzyme, causing a change in the shape of the active site so that it can no longer interact with the substrate

hydrolysis reaction

a reaction that breaks down compounds by the addition of water

dehydration reaction

a reaction in which two compounds are brought together with water released as a product

endergonic reaction

a reaction that requires input of energy to occur

exergonic reaction

a reaction that gives off energy as a product

redox reaction

a reaction involving the transfer of elections. this reaction occurs along the electron transport chain of the mitochondria during respiration

cell

all living things are composed of these, discovered in the 17th century by Robert Hooke

plasma membrane

a selective permeability barrier around a cell (all cells have it) composed of a phospholipid bilayer studded with proteins and carbohydrates (fluid mosaic model)

cell wall

a barrier that functions to protect and give shape to the cell. present in all prokaryotes and plant cells

ribosomes

found in all cells, function in protein synthesis. they are loose in the cytoplasm in prokaryotes. but in eukaryotes can be either bound or free and are produced in the nucleolus

bound ribosomes

attached to rough endoplasmic reticulum and form proteins that tend to be exported from the cell or sent to the cell membrane

free ribosomes

float in the cytoplasm, produce protein that remain in the cytoplasm of the cell

smooth ER

a membrane-bound organelle involved in lipid synthesis, detoxification, and carbohydrate metabolism. liver cells contain a lot of this because it does a lot of gylcolysis (carbohydrate metabolism) and because it is the site of alcohol detozification. called what it's called because it has no ribosomes

rough ER

membrane bound organelle called what it is because it has ribosomes. the proteins produced by this organelle are often secreted by the cell and carried by vesicles to the golgi apparatus for further modification

golgi apparatus

proteins, lipids, and other macromolecules are sent here to be modified by the addition of sugars and other molecules to form glycoproteins. they are then sent in vesicles to other parts of the cell, directed by the particular changes made by it

mitochodria

double membraned organelles that specialize in the production of ATP. the innermost part of it is called the matrix, and the folds created by it are the cristae. it's the host organelle for the krebs cycle and and oxidative phosphorolation of respiration

lysosome

this is a membrane-bound organelle that specializes in digestion. it contains enzymes that break down (hydrolyze) proteins, lipids, nucleic acids, and carbohydrates. absence of of a particular lysosomal hydrolytic enzyme can lead to storage diseases. also known as "suicide sacs" because they digest cells that are no longer needed. ex. cells of a tadpole's tail as it changes to a frog

nucleus

this is the control center of the cell. the storage site of genetic material in the form of DNA. the site of replication, transcription, and postranscriptional modification of RNA. and contains the nucleolus, the site of ribosome synthesis

vacuole

a storage organelle that acts as a vault. large in plant cells, small in animal cells

peroxisomes

these are organelles containing enzymes that produce hydrogen peroxide as a by-product while performing various functions, such as breakdown of fatty acids and detoxification of alcohol in the liver. they also contain an enzyme that converts the toxic hydrogen peroxide by-product of these reactions into water

chloroplast

the site of photosynthesis and energy production in plants. divided into inner and outer portion. inner fluid portion is the stroma. winding through the stroma is an inner membrane called the thylakoid membrane system where light dependent reactions occur. light independent reactions occur in the stroma

cytoskeleton

the skeleton of cells that contains three types of fibers that provide support, shape, and mobility to cells

microtubules

fibers constructed from tubulin and form a spindle in mitosis. they also are important components of cilia and flagella-plants do NOT have these

microfilaments

fibers made of actin play a big part in muscular contraction

intermediate filaments

fibers constructed from a class of proteins called keratins and are thought to function as reinforcement for the shape and position of organelles in the cell

fluid mosaic model

model fro the arrangement of the plasma membrane. a membrane consists of a phospholipid bilayer with proteins of various lengths lengths and sizes interspersed with cholesterol among the phospholipids.

intergral proteins

proteins implanted withing the bilayer and can extend partway or all the way across the membrane.

peripheral proteins

such as receptor proteins, which are not implanted in the bilayer and are often attached to intergral proteins

membrane protein functions

a channel to assist the passage of desired molecules into the cell, can act as receptors that allow the cell to respond to external signals (such as hormones) or they can be enzymes and increase the rate of cellular reactions

selective permeability rules

the membrane bouncer lets in small, uncharged polar molecules and hydrophobic molecules such as lipids, but larger, uncharged molecules (glucose) and charged ions (sodium) cannot pass. and the particular arrangement of proteins in the membrane. different arrangements allow different molecules to pass through

diffusion

the movement of molecules down their concentration gradient without the use of energy. a passive process during which molecules move from high concentration to low concentration. the rate of this varies membrane to membrane because of different selective pereabilities

osmosis

the passive diffusion of water down its concentration gradient across selectively permeable membranes. from high to low water concentration. water moves from hypotonic (dilute) to hypertonic (concentrated) no energy required

active transport

the movement of a particle across a selectively permeable membrane against its concentration gradient. this requires the input of energy. ATP is used. this process is vital to the ability of cells to maintain particular concentrations of substances despite environmental conditions. ex. cells have a large concentration of potassium and low concentration of sodium. the sodium potassium pump helps the cell maintain those levels in animal cells

endocytosis

a process in which substances are brought into cells by the enclosure of the substance into a membrane-created vesicle that surrounds the substance and escorts it into the cell. it's used by immune cells called phagocytes to engulf and eliminate foreign invaders.

exocytosis

a process in which substances are exported out of the cell. the vesicle escorts the substance to the plasma membrane, fuses with the membrane, and ejects the contents out of the cell.

facilitated diffusion

the diffusion of particles across a selectively permeable membrane with the assistance of the membrane's transport proteins. they have a binding site designed for molecules of interest, does not require energy

aerobic respiration

glycolysis then krebs cycle then oxidative phophorolation

anaerobic respiration

glycolysis then fermentation

glycolysis

occurs in the cytoplasm of cells and is the beginning pathway for both aerobic and anaerobic respiration. a glucose molecule is broken down through a series of reactions into two molecules of pyruvate. no oxygen required. but in oxygen-poor environments, this process is really slow because the cells become depleted of NADplus. lack of oxygen prevents oxidative phosphorolation, causing a buildup of NADH. this buildup causes a shortage of NADplus. this is bad because it requires NADplus to function-fermentation is the solution

glycolysis products

two molecules each of ATP, NADH, and pyruvate from 1 glucose molecule

krebs cycle

krebs cycle

oxidative phophorolation

oxidative phophorolation

electron transport chain

electron transport chain

chemiosmosis

chemiosmosis

ATP synthase

ATP synthase

fermentation

fermentation

mesophyll cells

where the majority of chloroplasts are found

bundle-sheath cells

cells tightly wrapped around the veins of a leave (the site of the calvin cycle in C4 plants)

C4 plant

plant that has adapted its photosynthetic process to more efficiently handle hot and dry conditions

mesophyll

interior tissue of a leaf

photolysis

process by which water is broken up by an enzyme into hydrogen ions and oxygen atoms; occurs in the light-dependent reactions

photophosphorylation

process by which ATP is produced during the light-dependent reactions. (chloroplast equivalent of oxidative phophorolation)

photorespiration

process by which oxygen competes with carbon dioxide and attaches to RuBP. plants that experience this have a lowered capacity for growth

photosystem

a cluster of light-trapping pigments involved in the process of photosynthesis. they vary tremendously in their organization and can possess hundreds of pigments

pigment

a molecule that absorbs light of a particular wavelength. they are vital to process of photosynthesis and include chorophyll, carotenoids, and phycobilins

rubisco

an enzyme that catalyzes the first step of the calvin cycle in C3 plants

transpiration

natural process by which plants lose water through evaporation through their leaves

light dependent reaction

it occurs in the thylakoid membrane, its inputs are water and light, it produces ATP, NADPH, and oxygen, the oxygen comes from water, not carbon dioxide

chlorophyll a

the major pigment of photosynthesis

chlorophyll b

accessory pigment

cell cycle

G1, S G2, M

G1

the first growth stage of the cell cycle. the cell prepares itself for synthesis, making sure it has all the necessary materials for DNA synthesis

S

DNA is duplicated at this stage so that each daughter cell has has a complete set of chromosomes

M

mitosis, cell division stage

G2

second growth phase, cell prepares itself for mitosis/meiosis, making sure it has all the materials necessary for the physical separation and formation of daughter cells

interphase

G1, S, G2; 90% of the cycle

prophase

nucleus and nucleolus disappear at this stage, chromosomes appear as two identical, connected sister chromatids, mitotic spindle (microtubules) begins to form, centrioles move to opposite poles of the cell--but plant cells do not have centrioles

metaphase

the sister chromatids line up along the middle of the cell, ready to split apart

anaphase

the split sister chromatids move via the microtubules to the opposing poles of the cell, pulled by the spindle apparatus. now each pole of the cell has a complete set of chromosomes

telophase

the nuclei for the newly split cells form, the nucleoli reappear, and the chromatin uncoils

cytokinesis

newly formed daughter cells split apart. animal cells by the formation of a cleavage furrow, plant cells by the formation of a cell plate

cell plate

plant cell structure, constructed in the golgi apparatus, composed of vesicles that fuse togeter along the middle of the cell, completing the separation process

cyclin

a protein that accumulates G1, S, and G2

protein kinase

a protein that controls other proteins through the addition of phosphate groups

CDK

cyclin-dependent kinases; present at all times throughout the cell cycle and binds with cyclin to form a complex known as MPF (mitosis promoting factor) as the concentration of cyclin reaches a certain level, enough MPF is formed to push the cell into mitosis and the amount of cyclin decreases, pushing the cell out of mitosis

prophase I

each chromosome pairs with its homolog. crossover occurs in this phase. the nuclear envelope breaks apart, and the spindle begins to form

metaphase I

chromosomes align along the metaphase plate matched with their homologous partner. the stage ends with the separation of the pairs

anaphase I

separated homologous pairs move opposite poles

telophase I

nuclear membrane reforms, the process of division begins

cytokinesis

after the daughter cells split, the two newly formed cells are haploid

prophase II

the nuclear envelope breaks apart and the spindle begins to form

metaphase II

sister chromatids line up along the equator of the cell

anaphase II

sister chromatids split apart and are called chromosomes as they are pulled to the poles

telophase II

the nuclei and the nucleoli for the newly split cells return

sporophyte

diploid stage of plants

gametophyte

haploid organism (plants)

law of segregation

the two alleles for a trait separate during the formation of gametes-one to each gamete

law of independent assortment

inheritance of one trait does not interfere with the inheritance of another trait

allele

a variant of a gene for a particular character

genotype

an organism's genetic makeup for a given trait

karyotype

a chart that organizes chromosomes in relation to number, size, and type

nondisjunction

the improper separation of chromosomes during meiosis, which leads to an abnormal number of chromosomes in offspring (down, turner, and klinefelter syndromes)

phenotype

the physical expression of the trait associated with a particular genetic cross

incomplete dominance

red + white = pink, hypercholersterolemia, sickle cell

codominance

roan (red and white hair), my hairline, MN blood type

polygenic traits

traits affected by more than 1 gene (eye color, skin tone)

multiple alleles

blood

epistasis

the expression of one gene affects the expression of another

pleiotriohy

a single gene has multiple affects on an organism-sickle cell, how it causes heart, lung, and kidney damage, muscle pain, weakness, and generalized fatigue, and kidney failure

Duchenne's muscular dystrophy

a sex-linked disorder caused by the absence of an essential muscle protein. symptoms include a progressive loss of muscle strength and coordination

hemophilia

sex-linked disorder caused by the absence of a protein vital to the clotting process (Anastasia and the Romanovs)

red-green colorblindness

sex-linked, primarily in males, cannot distinguish between certain colors

x-inactivation

females have two x chromosomes, but only one is active, the other becomes a barr body, and its genes are not expressed

holanderic traits

traits inherited via the y chromosome (ear-hair distribution)

linked genes

genes that tend to be inherited together. they lie on the same chromosome and do not follow the law of independent assortment

linkage map

a genetic map put together using crossover frequencies

map unit

also called a centrigram, is used to geographically relate the genes on the basis of crossover frequencies

Tay-Sachs disease

a fatal genetic disorder that renders the body unable to break down a particular type of lipid that accumulates in the brain and eventually causes blindness and brain damage. found in a large percentage of easter european jewish descent

cystic fribrosis

a recessive disorder located on chromosome 7. the normal allele for this gene is involved in cellular chloride ion transport. a defective version of this gene results in the exessive secretion of a thick mucus, which accumulates in the lungs and digestive tract

sickle cell amemia

a common recessive disease that occurs as a result of an improper amino acid substitution during translation of hemoglobin, resulting in deformed hemoglobin and red blood cells. very common because heterozygous individuals are resistant to malaria (herterozygote advantage) increasing their chances of survival

PKU

phenylketonuria, an autosomal recessive disease caused by a single gene defect, making one unable to digest phenylalanine (an amino acid) leading to an accumulation of a by-product in the blood, causing mental retardation

huntington's disease

a dominant disorder, causing the breakdown of the nervous system

down syndrome

trisomy 21, an example of aneuploidism, leads to mental retardation, sterility, heart defects, short stature, and characteristic facial features.

aneuploidy

the condition of having an abnormal number of chromosomes

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