EK B1 Ch1 Biological molecules COPY

Question 1

glycine

Answer 1

• smallest amino acid, contains a hydrogen atom as the side chain- contributes to the structure n function of proteins-necessary for the synthesis of heme, an iron-containg molecule required for hemoglobin function in red blood cells

Question 2

glutamate, and derivatives of amino acid tyrosine

Answer 2

• are important for signalng molecules in the brain and function as neurotransmitters

Question 3

glutamine and alanine

Answer 3

• required for metabolic pathways involved in nitrogen metabolism

Question 4

amphipathic molecules

Answer 4

polar and nonpolar chemical properties contained within the same moleculefatty acids - consist of carobxyl group (polar) attached to an end hydrocarbon chain (nonpolar)

Question 5

fatty acids in living cells primarily act…..

Answer 5

as components of plasma membrane lipids, which form a hydrophobic barrier separating the aqueous phases of the inside and outside of cells.

Question 6

saturated fatty acids

Answer 6

have NO C=C double bonds in hydrocarbon chain

Question 7

unsaturated fatty acids

Answer 7

have C=C double bonds

Question 8

phospholipids

Answer 8

The most abundant lipids in cell membranes are phospholipids, which generally contain a simple organic molecule attached to a negatively charged phosphoryl group and two fatty acids. Besides the plasma membrane, eukaryotic cells (plant and animal cells) contain a variety of intra- cellular membranes consisting of fatty acid–derived lipids. These include the nuclear membrane, the inner and outer mitochondrial and chloroplast membranes, and mem-branes associated with the endoplasmic reticulum and Golgi apparatus

Question 9

ATP levels…

Answer 9

ATP levels inthe cell are a measure of available energy because a large number of biochemical reactions depend on phosphoryl transfer energy made available from ATP hydrolysis.

Question 10

triacylglycerols

Answer 10

Another important function of fatty acids in eukaryotes is as a storage form of energy, which is made possible by their highly reduced state. Fatty acids yield chemical energy upon oxidation in mitochondria. Used for energy storage in this way, fatty acids are converted to triacylglycerols and sequestered in the adipose tissue of animal cells, whereas plants store triacylglycerols in seeds. Triacylglycerols are neutral (uncharged) lipids that contain three fatty acid esters covalently linked to glycerol. Lastly, fatty acids and fatty acid–derived molecules have recently been shown to be important signaling molecules that bind to nuclear receptor proteins. In this way, fatty acids regulate lipid and carbohydrate metabolism, inflammatory responses, and cell development.

Question 11

peptide bond

Answer 11

any of 20 different amino acids can be linked together by a covalent bond called a peptide bond (Figure 1.11). Polypeptide chains also have polarity, as they contain an amino group on one end and a carboxyl group on the other. Therefore, the number of octamer polypeptides that can theoretically be assembled with any one of the 20 amino acids at each position is a staggering 208, or 2.58 × 1010 different protein sequences. However, the actual number of different polypeptide sequences encountered biologically is much smaller than the theoretical number because not all combinations of amino acids have useful structural and functional properties due to differences in the size and chem- istry of their side chains.

Question 12

Chitin

Answer 12

-is another abundant carbohydrate polymer found in nature, is a major component in the exoskeletons of many invertebrates (insects and crustaceans) and in the cell walls of some types of fungi. Chitin consists of repeating N-acetylglucosamine units, a derivative of glucose, linked together by the same type of β(1→4) glycosidic bonds found in cellulose. Many types of bacteria contain the enzyme chitinase, which is able to cleave the β(1→4) glycosidic bond in chitin and thereby facilitate decomposition processes.

Question 13

The polysaccharides amylose and cellulose contain….

Answer 13

…..the same repeating unit of glucose,but differ in the structure of the glycosidic bond linking adjacent units (shown in red). p. 15 a. Amylose (starch) is a polymer of glucose containing α(1→4) glycosidic bonds between glucose units.b. Cellulose, contained in plant cell walls,is identical in composition to amylose; however, the glycosidic bonds between glucose units arein the β(1→4) configuration,and adjacent glucose residuesare rotated 180°.

Question 14

bacteria cell wall

Answer 14

The bacterial cell wall itself is coated with either a capsule or a slime layer that aids in enabling the bacterium to attach to other cells or solid surfaces.

Question 15

bacteria cytoplasm

Answer 15

The cytoplasm of the bacterial cell contains all of the enzymes required for cell metabolism, as well as the chromosome, which consists of DNA compacted with nucleic acid binding proteins to minimize its size.

Question 16

bacteria chromosome

Answer 16

The bacterial chromosome is circular and localized to a region in the cell called the nucleoid.

Question 17

bacteria cytoplasm

Answer 17

also contains proteins involved in cell division and the assembly of extracellular structures, such as flagella and pili, which are used for cell movement.

Question 18

bacteria plasmid

Answer 18

Many types of bacteria contain one or more circular DNA molecules called plasmids, which may encode genes involved in cell mating or antibiotic resistance. The plasmid replicates independently of the bacterial chromosome. Recombinant DNA methods make use of bacterial plasmids for gene cloning.

Question 19

what is the size of eukaryotic cells versus prokaryotic cells

Answer 19

Note that the diameter of eukaryotic cells is as large as ∼10–100 μm, whereas the diameter of prokaryotic cells is only ∼1 μm. so eukaryotic cells are 10-100 times larger than most bacteria

Question 20

Bacteria are prokaryotic cells with……

Answer 20

a cytosolic compartment surrounded by a plasma membrane that forms a barrier separating the cell from the environment. Most bacteria contain a single circular chromosome and move using flagellar structures or pili located on the outside of the cell.

Question 21

Animal cells differences/ what makes them special

Answer 21

Animal cells are a type of eukaryotic cell and contain numerous intracellular membrane-bound compartments, which create microenvironments for biochemical reactions. Membrane-bound organelles in all types of eukaryotic cells include mitochondria, lysosomes, and peroxisomes, which are subcellular sites for specific metabolic reactions. ** why they are on the outside**

Question 22

Plant cell differences/ what amkes them special

Answer 22

Plant cells are eukaryotic cells that contain chloroplasts, which convert light energy into chemical energy by the process of photosynthesis.Plant cells also contain large vacuoles, which are responsible for maintaining metabolite pools. The plasma membrane of plant cells is surrounded by a cell wall consisting of cellulose, which provides structural integrity to the plant.vacuoles are very large membrane bound**remember Both mitochondria and chloroplasts contain their own genomic DNA, which encodes pro- teins required for organelle function. ***

Question 23

chromatin (euk)

Answer 23

eukaryotic DNA is packaged with proteins to form a structure called chromatin that is contained within a membrane-bound region of the cell called the nucleous

Question 24

nucleolus

Answer 24

which is where ribosomes are assembled from ribosomal RNA and protein

Question 25

ribosomes

Answer 25

Ribosomes are large RNA–protein complexes that mediate proteins syntehsis in prokartyotic and eukartoic cells

Question 26

ER

Answer 26

rough adn smooth–> which are highly invaginated membrane structures that sequester ribosomes for protein synthesis.

Question 27

Golgi apparatus

Answer 27

is a membranous structure involved in protein translocation within the cell and in facilitating protein secretion at the plasma membrane.

Question 28

mammalian macrophage cells

Answer 28

are protective cells in the immune system that seek out and destroy invading microorganisms or abnormal cells based on identification of foreign cell surface proteinsare immune cells in animals that engulf microorganisms such as bacteriaMicrophages use pseudopodia to recognize foreign or abnormal cells based on cell surface proteins

Question 29

endosymbiotic theory

Answer 29

proposes that eukaryotic cells evolved about 1.5 billion years ago as a result of large predatory cells engulfing aerobic bacteria, which eventually gave rise to mitochondria. The symbiotic bacteria were able to use O2 in the atmosphere as an electron acceptor in oxidation–reduction reactions, which provided a form of chemical energy for the synthesis of ATP. The predatory cells benefited from the extra ATP produced by the symbiotic bacteria, which in turn were rewarded with a nutrient-rich environment. Supportive evidence for the endosymbiotic theory comes from DNA sequence similarities between mitochondrial and bacterial genomes that have been analyzed using computational methods.

Question 30

liver

Answer 30

metabolic control center

Question 31

skeletal muscle

Answer 31

mechanical work and glucose homeostasis

Question 32

intestines

Answer 32

nutrient absorption

Question 33

adipose tissue

Answer 33

energy storage and hormonal signaling

Question 34

kidneys

Answer 34

water, nitrogen, and electrolyte balance

Question 35

How does the molecule glucose fit into the seven hierarchical levelsthat define the chemical basis of life on Earth?

Answer 35

Glucose is a biomolecule that contains three of the most abundant elements in living systems: carbon, oxygen, and hydrogen. Amylose and cellulose are polymers of glucose, and glucose biosynthesis is maintained by highly regulated metabolic pathways. Glucose is the primary component of plant cell walls and can be stored for energy needs in plant and animal cells in the form of starch and glycogen, respectively. The circulatory systems of multicellular organisms, such as mammals, transport glucose between tissues, which primarily use this metabolite for energy conversion processes (glycolytic path- way to generate ATP). Flowers contain nectar, a rich source of glucose (and fructose), which is used by honeybees as a nutrient source; when honeybees retrieve nectar, they cross-pollinate plants to help build a healthy ecosystem.

Question 36

nucleotides (the building blocks of nucleic acids) are made up of 3 THINGS

Answer 36

• a nucleotide base (adenine, guanine, cytosine, thymine, or uracil); • a five-carbon ribose or deoxyribose sugar• one or more phosphate groups.

Question 37

Nucleotides are the building blocks of nucleic acids……. details about them

Answer 37

The common nucleotides in DNA and RNA contain a nucleotide base attached to the 1′-carbon of the ribose sugar and a phosphoryl group attached to the 5′-carbon. The 2′-carbon of ribonucleotides contains a hydroxyl group, whereas deoxyribonucleotideshave a hydrogen atom in this position.-G-C base pairs contain three hydrogen bonds.- A-T base pairs in DNA–DNA hybrids contain two hydrogen bonds. -A-U base pairs in DNA–RNA duplexes or RNA–RNA duplexes contain two hydrogen bonds. Hydrogen bonds are shown as dashed red lines between the base pairs.

Question 38

key differences DNA vs RNA

Answer 38

Deoxyribonucleotides are the monomeric units of DNA and lack a hydroxyl group on the carbon at the 2′ position (C-2′) of the ribose sugar, whereas ribonucleotides in RNA contain a hydroxyl group in this same position. As originally proposed by Watson and Crick and later confirmed by high-resolution X-ray crystallography, the DNA double helix contains two single polynucleotide strands that interact noncovalently to form a duplex. These strands are noncovalently associated through hydrogen bonds between the nucleotide bases, forming a duplex structure. The deoxyribonucleotide base pairs in DNA consist of guanine hydrogen-bonded to cytosine (G-C or C-G base pair) and adenine hydrogen-bonded to thymine (A-T or T-A base pair)RNA lacks the nucleotide base thymine and instead contains the nucleotide base uracil, which hydrogen bonds with adenine (A-U or U-A base pair)Because the chemical structures of nucleic acids are very similar, hybrid molecules of DNA and RNA can form, provided they contain complementary nucleotide bases to form G-C, A-T, or A-U base pairs

Question 39

hydrogen bond

Answer 39

Hydrogen bonds are a type of weak non-covalent interaction in which a hydrogen atom is shared between polar groups.

Question 40

polarity of DNA strands

Answer 40

The polarity of each DNA strand is determined by the bonds between the ribose and phosphate groups, which form the sugar–phosphate backbone.Two antiparallel DNA strands are held in register relative to each other by the hydrogen bonds between the nucleotide base pairs.

Question 41

How genome is copied….

Answer 41

1. DNA replication2. DNA transcription

Question 42

DNA replication

Answer 42

requires that DNA/genome be faithfully copied by a process called DNA replication and that segments of DNA, known as genes, be converted into RNA by DNA transcription. - so genome is copied during cell division by this process

Question 43

DNA transcription

Answer 43

• genes are converted into RNA by DNA transcription. Genes are functional units of DNA that are defined by the RNA products they produce. A variety of RNA products are generated by DNA transcription, one of which is mRNA, which is used to synthesize proteins by mRNA translation. The majority of RNA produced by DNA transcription is required for protein synthesis (rRNA and tRNA), RNA processing (snRNA), and regulation of gene expression or protein synthesis (miRNA). Under some conditions, RNA molecules can also be converted back into DNA by reverse transcription.

Question 44

mRNA

Answer 44

A subset of the gene-encoded RNA molecules are called messenger RNA (mRNA) molecules. These are used as templates for protein synthesis in a process referred to as mRNA translation.DNA sequences are transcribed into mRNA by the enzyme RNA polymerase in the nucleus of eukaryotic cells. RNA polymerase synthesizes mRNA using ribonucleotides that form complementary base pairs with deoxyribonucleotides in the template strand of DNA. -The DNA sequence of the coding strand is the same as the RNA sequence in the mRNA, with the exception of uridine replacing thymidine. -The mRNA is then exported to the cytoplasm, where it is translated into protein.

Question 45

mRNA translation

Answer 45

the TRANSLATION of mRNA requires a protein-synthesizing complex, which consists of ribosomes, tRNAs, and the mRNA. -Charged tRNAs bring amino acids into the ribosome complex, where they form complementary base pairs with the mRNA through codon–anticodon hydrogen bonds-Once the amino acid has been covalently linked to the growing polypeptide chain, the uncharged tRNA exits the ribosomal complex, making room for the next charged tRNA.

Question 46

in addition to mRNA, cells also contain small nuclear RNA (snRNA) molecules

Answer 46

which are involved in RNA processing

Question 47

micro RNA (miRNA) molecules

Answer 47

regulate gene expression and mRNA translation

Question 48

The most abundant RNA molecules in cells are……

Answer 48

ribosomal RNA (rRNA) molecules and transfer RNA (tRNA) mRNA translation molecules both of which are required for protein synthesis in addition to mRNA

Question 49

reverse trancription

Answer 49

converts RNA into DNA, still defined by the central dogma of molecular biology

Question 50

In eukaryotic cells, the process of DNA transcription takes place

Answer 50

In eukaryotic cells, the process of DNA transcription takes place in the cell nucleus and leads to the production of mRNA transcripts. These transcripts are exported to the cytoplasm, where they are translated into polypeptide chains

Question 51

In prokaryotic cells, DNA transcription and mRNA translation take place

Answer 51

in the cytosol, with mRNA molecules being translated as soon as they are synthesized.

Question 52

Dna transcription 2

Answer 52

the DNA sequence in the template strand forms complementary base pairs with the ribonucleotide sequence in the mRNA strand. (For example, the DNA sequence 3′-TAC-5′ corresponds to 5′-AUG-3′ in RNA.) In contrast, the DNA sequence in the non-template, or coding strand, is identical to the mRNA sequence, with the exception of uracil replacing thymine-After export to the cytoplasm, the mRNA is translated by ribosomes, which consist of proteins and rRNA. The ribosomes serve as binding sites for charged tRNA molecules, which deliver amino acids to the protein-synthesizing complex.

Question 53

If the mutation is passed from the parents to their offspring…

Answer 53

then the mutation is contained within the DNA of a germ-line cell (egg and sperm cells in eukaryotes) and is referred to as an inherited genetic disease.

Question 54

if the DNA mutation occurs during the lifetime of the organism in a somatic cell

Answer 54

somatic cells= all cells that are not germ cells…then the consequences of this mutation—the disease phenotypes—are limited to the individual organism and are not inherited by its offspring. Tay–Sachs disease (a disorder of the nervous system) is an example of an inherited genetic disease, whereas most forms of cancer, such as the most common types of lung and colon cancer, are the result of DNA mutations that occur in damaged somatic cells.

Question 55

orthologous genes

Answer 55

Highly conserved gene sequences that encode proteins with the same function in different organisms they are thought to have risen from a common ancestral gene

Question 56

Gene sequences evolve much more slowly……

Answer 56

than DNA sequences located between genes because natural selection provides a mechanism to preserve useful gene functions. Random nucleotide mutations that have no major effect on gene expression and function accumulate in flanking DNA at much higher rates than deleterious mutations accumulate within genes, the latter being eliminated by natural selection.

Question 57

ex. The glucose- 6-phosphate dehydrogenase gene

Answer 57

is an orthologous gene in bacteria, yeast, worms, flies, and humans, with very high amino-acid-sequence conservation in regions of the protein required for enzymatic function. The consensus sequence identifies amino acid residueswithin the aligned sequencesthat are identical (*), chemically conserved substitutions (:), or chemically related substitutions (.). p. 31

Question 58

The protein glucose-6-phosphate dehydrogenase

Answer 58

is important in providing cells with a biomolecule called nicotinamide adenine dinucleotide phos- phate (NADPH; reduced form), which is required for oxidation–reduction reactions in cells. Glucose-6-phosphate dehydrogenase also has a critical role in the metabolism of ribose sugars, which are required for the backbone of nucleic acids. The fact that the amino acid sequence for this protein has gone unchanged for so long is evidence of its importance and of the long-term success of its efficient functioning.

Question 59

paralogous genes

Answer 59

Bioinformatic analyses suggest that in many cases, the second gene is, in fact, selectively retained and evolves to encode a protein with a related but distinct function. Related genes within a species are called paralogous genes and are considered members of a gene family. One ex is the nuclear receptor gene family, which encodes steroid receptor proteins that function as transcription factors (Figure 1.29b). Another example of paralogous genes is the globin gene family, which encodes proteins involved in oxygen transport.

Question 60

photosynthetic autotrophs

Answer 60

use solar energy to oxidize H2O and produce O2 generating chemical energy in the form of glucose (C6H12O6). The plant uses this glucose at night for metabolic fuel to sustain aerobic respiration. solar energy is produced by thermonuclear fusion reactions (conversion of hydrogen to helium) in the Sun for the process of photosynthesis, which provides the necessary energy for life during the daylight hours and for carbon fixation.

Question 61

Heterotrophs

Answer 61

cannot convert solar energy into chemical energy directly and therefore depend on photosynthetic autotrophs to generate the O2 and glucose needed for aerobic respiration and to provide those essential nutrients required for life that heterotrophs cannot synthesize themselves.

Question 62

photosynthesis

Answer 62

the process of oxidizing H2O to capture chemical energy and generate O2 is called photosynthesis

Question 63

carbon fixation

Answer 63

is the conversion of Co2 to organic compounds

Question 64

Both heterotrophs and photosynthetic autotrophs use

Answer 64

O2 and glucose (C6H12O6) for the process of aerobic respiration, which is a form of chemical energy conversion. Oxidation of H2O by photosynthetic organisms is the primary source of O2 in our atmosphere.

Question 65

The first law of thermodynamics states

Answer 65

that the total amount of energy in the universe remains the same, even though the form of energy may change. Put another way, energy can neither be created nor destroyed, only transformed (converted).

Question 66

The second law of thermodynamics states that

Answer 66

in the absence of an energy input, all spontaneous processes in the universe tend toward dispersal of energy (disorder), and moreover, that the measure of this disorder, called entropy, is always increasing in the universe. It is important to note that all biological energy conversion processes (as well as all mechanical energy conversion processes) are less than 100% efficient; some of the converted energy is lost as heat rather than used for work.

Question 67

EKhydrolysis

Answer 67

reaction where a macromolecule such as a protein is broken into two smaller molecules through the addition of water MACROMOLECULES BROKEN APART lysis–> separation- they hydrolysis of ATP molecules provides the body’s major source of energy, digestion is primarily the hydrolysis of macromolecules*** breaking a bond by adding the H and OH of water of either endhere is an example where water can act as a reactant or product compared to whne it acts in other scenarios as the solvent

Question 68

dehydration

Answer 68

• two molecules are combined to form a larger molecule and water is formed as a byproduct***COMBINATION OF TWO MOLECULES-reverse reaction of hydrolysis - this allows the formation of the bonds that make up biological molecules like PEPTIDE BONDS that make proteins and ESTER BONDS that are essential to triglycerides

Question 69

ATP Hydrolysis

Answer 69

* remember that here water serves as a nuc and attacks the electrophilic phosphoanhydride bond between the beta and Y phosphates of hte ATP molecule- the freed Y phosphate can then be used by a kinase enzyme to phosphorylate target proteins

Question 70

water molecules hdyrogen bonding properties

Answer 70

• the ability of water molecules to form H bonds with each other elevates the boiling point - so water remains in a liquid state as a result*** in teh cellular enviornment

Question 71

Hydrophobic

Answer 71

• Greek hydros= water, phobos=fear- H bonding also provides strong cohesive forces between water molecules “squeezing” hydrophobic molecules away from water and causing them to aggregate

Question 72

hydrophilic

Answer 72

hydros=watergreek philos= love- molecules or ionic compounds dissolve easily in water because their negatively charged ends are attracted to the partial positive charge of water’s hydrogens while their posiitivelyt charged ends are attrcted to the partial negative charge of the oxygen- water moelcules surround (solvate) a hydrophilic molecule or ion

Question 73

EK Lipids

Answer 73

• low solubility in water and high solubility in non-polar organic solvents**- lipids are non-polar and therefore hydrophobic- this property determines the behavior of lipids in the watery environment of the cellmajor lipids:- fatty acids-triacylglycerolsphospholipidsglycolipidssteroidsterpenes (vitamin A)waxes

Question 74

EK Role lipids play

Answer 74

• 1. energy storage2. cellular organization and structure, particularly in the membrane3. provision of precursor molecules for vitamins and hormones

Question 75

Key function to remember for lipidsEK

Answer 75

*** long carbon chains allow energy storage******that fats assemble into barriers separating aqueous environments because they are hydrophobic and that lipids are useful as precursors for signaling molecules because they can pass through cellular membranes***

Question 76

EKfatty acids

Answer 76

• lipids-act as fuel for the body and are components of the cell membranes-are composed of long carbon chains truncated at one end by carboxylic acid-usually contain an even number of C, in humans hte max number of C in a fatty acid is 24-they can be saturated (no C-C double bonds) or unsaturated (one or more double C= C bonds)

Question 77

EKtriacylglycerols

Answer 77

simply fats and oils***-constructed from a 3 C backbone called glycerol, which is attatched to three fatty acid chains-their function is to store energy in a cell- they can also provide thermal insulation adn padding to an organism

Question 78

EK adipocytes

Answer 78

latin adips=fatgreek kytos= cellfat cellsspecialized cells whose cytoplasm contains almost nothing but triglycerides

Question 79

EK phospholipids

Answer 79

• lipids with a phosphate group attachted, most important is phosphoglycerides which are built from a glycerol backbone like triglycerides but has a polar phospahte group replacing one fatty acidthe phosphate group lies on the opposite side of the glycerol from teh fatty acids , making phospholipid polar at the phosphate end an dnonpolar at the fatty endso this is amphipathic (Latin ambo= both)becuase polar and nonpolar ends, makes up membranes polar ends on the oustide, nonpolar C tails on the inside of membrane forms a barrier to polar molecuels that allows the regulation of their passage in and out of the cell

Question 80

EK glycolipids

Answer 80

similar to phosphoglycerides but with en or mroe carbohydrates attatchd to the three C glycerol backbone instead of a phosphate groupalso amphipathic

Question 81

EK sphingiolipids

Answer 81

same as phosphoglycerides with long chain fatty acid adn polar head group, but the backbone is an amino alcohol called sphingosine rather than glycerol - make up cell membrane like phospholipids, steroids, and glycolipids

Question 82

EK steroids

Answer 82

4 ringed structures, like hormones, cholesterol and vitamin D cholesterol is v important to maintain membrane stability and fluidity and serves as the precursor for steroid hormones

Question 83

EK waxes

Answer 83

formed by an ester linkage btw a long chain alcohol and a logn fatty acid chainwater repellent texture

Question 84

Ek key functions of lipids

Answer 84

1. phospholipids serve as a structural component of membranes2. triacylglycerols store metabolic energy adn provide thermal insulation and padding3. steroids regulate metabolic activity4. some fatty acids (eicosanoids, like prostaglandins) even serve as local hormones

Question 85

EK carbs

Answer 85

-useful for storing energy and providing easily accessible energy to the body- liek with fats high concentration of C-H bonds in carbs allow for the storage of a large amount of energy up to 4 kcal/mol which is less than half the energy content of fatty acidscarbs do not store as much energy per gram as lipids simply because they do nto have as high a concentration of C-H bonds, alcohols are also present in teh carbon chainconsistent structure of carbs allows them to stack together in a cell which contributes to their usefulness for energy storagestructure of carbs allows them to join together through dehydration reaction forming long chains of polysacchrides for energy storage, reverse of this is hydrolysis reaction allows the release of single sugar molecules monosacchrides which the tissues use for energyglucose and fructose are most important exs

Question 86

EK Cn(H2O)n

Answer 86

carbs can be thought of as carbon and water in a fixed one to one ratio, for each carbon atom there exists one oxygen atom and 2 HFOR ANY CARB this is the formula

Question 87

EK glycogen

Answer 87

• branched glucose polymer with alpha linkages found in all animal cells but large amounts are found in muscle and liver cells like most animals humans have enzymes to digest the alpha linkages of starch and glycogen but do not hav enzyme that can digest the beta linkages of cellulose (like grass) but cows do have bacteria in digestive system that release enzyme to digest the beta linkages in cellulose

Question 88

glucose/ATP

Answer 88

cell can oxidize glucose to transfer chemical energy to a more readily usable form ATP- if cell already has sufficient ATP glucose is polymerize dot the polysaccahride form glycogen or converted to fat

Question 89

disulfide bonds

Answer 89

can stabilize proteins but are not DNA helix

Question 90

Van der Waals

Answer 90

sum of the attractive and repulsive forces, not including covalent electrostatic interactions btw molecules

Question 91

rule of thumb

Answer 91

hte more polar a molecule the greater hte dipole moment and consequently the stronger the intermolecular forcces-this is hwy at STP, water which can hydrogen bond is a liquid which carbon dioxide is a gas, which is nonpolar-the larger the molecule the more likely it is to have trong intermolecualr forces, indepdent of its polarity, take the alkanes as an example. the simplest alkane, methane CH4 is a gas at STP, moving up ins ize hexans C6H14 is a liquid, as the size of the chain inc even more like eicosane C20H42 is found as a solid at STP, in fact most waxes used for candles are long chain alkanes

Question 92

beta sheet, alpha helix

Answer 92

• secondary structure
• are reinforced by H bonds btw carbonyl oxygen of one amino acid and hte hydrogen on the amino group of another
• a single protein can contain both structures at various locations along its chain
• these areas contribute to conformational or overall shape

Question 93

tertiary structure proteins

Answer 93

3d shape formed by curls and folds of peptide chain, 5 forces contribute to 3rd structure

1. covalent disulfide bonds btw two cystine amino acids on different parts of the chain, creating dimer cystine
2. electrostatic (ionic) interactions, mostly btw acidic and basic side chains like aspartic acid)
3. H bonds
4. van der waal forces
5. hydrophobic or nonpolar side chains pushed away from water toward center of the protein, hydrophobic bonding

Question 94

proline

Answer 94

turns that disrupt both alpha helix + beta pleated sheet formation are induced by proline because its physical structure, the R group binds to amine group, causing proline to be more rigid than a typical amino acid, causes kinks!
-binding prevents Pro from acting as H bond donor, causing formation of kinks that disrupt both alpha helices and beta-pleated sheets

Question 95

protein folding….

Answer 95

gathering of hydrophobic R groups away from the surrounding water is highly favorable because it allowed a decrease in the size of the highly ordered solvation layer, INC entropy of the system

Question 96

denatured

Answer 96

when native conformation is disrupted protein is said to be denatured
-lost most of its 2, 3,4 structure

Question 97

two types of proteins

Answer 97

structural made from long polymers like collagen, and globular proteins like enzymes, hormones, membrane pump and channels etc.

Question 98

denaturing agent: urea

Answer 98

forces disrupted is Hydrogen bonds

Question 99

denaturing agent: salt or change in pH

Answer 99

forces disrupted is electrostatic bonds

Question 100

denaturing agent: beta- mercaptoethanol

Answer 100

forces disrupted is disulfide bonds

Question 101

denaturing agent: organic solvents

Answer 101

forces disrupted is hydrophobic forces

Question 102

denaturing agent: heat

Answer 102

all forces are disrupted

Question 103

microtubules

Answer 103

make up Eu flagella (only thing with flagella is sperm) and cilia
- made from globular tubulin, which polymerizes under the right conditions to become structural protein

Question 104

glycoproteins

Answer 104

proteins which carbohydrate groups attached

• AB antigens on red blood cells that determine an individual’s blood type are examples of glycoproteins. These are a component of cellular plasma membranes and are generally more than 50% protein
• whenever see “glyco” think sugar, so proteins with sugars attached

Question 105

cytochrome

Answer 105

• kytos= cell, chroma= color or pigment ) are proteins which require a protesthetic, heme, haima= blood, group in order to function
• get their name from color that they add to the cell
• ex are hemoglobins and cytochromes of the ETC in inner membrane of mitochondria

Question 106

proteoglycans

Answer 106

mixture of proteins and carbohydrates, generally consist of more than 50% carbohydates
- major component of extracellular matrix

Question 107

conjugated proteins

Answer 107

-proteins containing nonproteinaceous components are called conjugated proteins!

Question 108

Translation 1

Answer 108

Translation is the process in which an mRNA sequence is translated into a protein, with each codon corresponding to an amino acid. Transfer RNA, or tRNA, is a relatively small RNA molecule characterized by a hairpin structure that is responsible for “translating” between codons and amino acids. The other structure needed for translation is the ribosome, which is primarily made up of ribosomal RNA (rRNA). Ribosomes contain multiple rRNA strands with associated proteins, and have two major components: the large subunit (50S in prokaryotes and 60S in eukaryotes) and the small subunit (30S in prokaryotes, 40S in eukaryotes), with overall sizes of 70S for the prokaryotic ribosome and 80S for the eukaryotic ribosome. The large subunit catalyzes the formation of the polypeptide chain, while the small unit reads the RNA.

Question 109

translation 2

Answer 109

Translation has three main steps: initiation, elongation, and termination. Initiation occurs when the mRNA sequence binds to the small ribosomal subunit, either at a region in the 5’ untranslated region known as the Shine-Dalgarno sequence (in prokaryotes) or to the 5’ cap in eukaryotes. The first tRNA is known as the initiator tRNA, and it binds to the start codon (AUG). The initial amino acid is methionine in eukaryotes, but N-formylmethionine in prokaryotes. Once this happens, initiation factors facilitate the binding of the small ribosomal subunit to the large ribosomal subunit, forming the initiation complex.

Question 110

Translation 3

Answer 110

Elongation is the next step. During elongation, the ribosome reads the mRNA in the 5’ to 3’ direction and synthesizes a polypeptide from its N terminus to its C terminus, which is one of the reasons why amino acid sequences are traditionally written in the N-to-C order. Proteins known as elongation factors help move this process along. Three main binding sites are involved in elongation. The A site contains the next aminoacyl-tRNA complex, and at the P site a peptide bond is formed between the growing polypeptide chain and the incoming amino acid. The tRNA, which is now no longer “charged” with an attached amino acid, briefly pauses at the E site and detaches from the mRNA. After all of the charged tRNA sequences have been translated, translation is terminated.