Bio Test 1
The function of the nucleus is
to store genetic information
Doubled-stranded DNA consists of two antiparallel strands, meaning that one strand is oriented in the 5' to 3' direction, while the other is oriented in the 3' to 5' direction.
true
Lysosomes function in the destruction and recycling of old organelles.
true
Water provides structural support due to its inability to be compressed.
turgid pressure in plants
isomers
two structures with an identical molecular formula but different structures and characteristics
chloroplasts
type of plastid, specialize plant organelle, site of photosynthesis, inner and outer membrane, membranes enclose thylakoids(disc like structure), grana (stack of thylakoids), and stroma (surrounds stacks of thylakoids like cytosol)
peroxisome
used in break down of fats and contains the enzyme catalase
motor proteins
uses ATP to move vesicles within cells, uses ATP to bend filaments
endomembrane system
uses vesicles to transport proteins, sorts proteins for secretion
hydrolysis
"bust up" with water; polymers broken into smaller units by adding water
mitochondria
"power plants" of the cell; sites of oxidative metabolism
monosaccharides
"simple sugars" 3 triose-glyceraldehyde 5 pentose-ribose and deoxyribose 6 hexose- glucose, fructose, and galactose(structural isomers)
Hydrogen bonding of water provide it with unique chemical properties that support life
1. High specific heat capacity 2. Cohesion and adhesion 3. Solid is less dense than liquid(expands when frozen) 4. Dissolves polar molecules 5. Dissociates into ions->pH
factors that influence protein folding and stability
1. hydrogen bonds: weak individually, strong together 2. ionic bonds 3. hydrophobic effects- go closer together(make a loop) 4. disulfide bridges 5. van der waals forces: maintain a perfect distance between each other
monomer to macromolecule 1. Nucleotide 2. Amino Acid 3. Monosaccharide 4. Fatty Acid
1. nucleic acid 2. protein 3. carbohydrate 4. lipid
protein hierarchy of structure
1. primary: linear sequence of amino acids 2. secondary: alpha helix or beta sheet folds depend on H bonds 3. tertiary: side chains interact 4. quaternary: multi polypeptide interaction
1. Trees take up water from their roots. Water must travel against ________ up to all the branches and leaves. 2. The _____ of water molecules, resulting from the ______ bonds between water molecules, causes a movement of the water through the plant's vessels, as it moves up from the roots. 3. As water _______ the pores of the leaves, more water is pulled up from below resulting in a constant supply of water moving up through the vessels of a plant.
1. surface tension 2. cohesion, hydrogen 3. evaporates from
microtubules
25nm in diameter and composed of alpha and beta tubulin proteins. They exhibit polarity with a positive and negative end.
Adding NH3 (ammonia) to water makes NH4+. What will be the general pH of this new solution, and what will happen to the ion concentrations?
Alkaline; decreased H+ ions and increased OH- .
_______ are the building blocks of proteins. They are made up of a center carbon atom bound to a positively charged ____ group and a negatively charged _____ group and a side chain.
Amino acids, amino, carboxyl
carbohydrates
C, H, O; c-h bond makes a good energy store, typically categorized as mono, di, and poly saccharrides;
The sequence that best describes the transportation of proteins through the endomembrane system is
Coat proteins form around the vesicle holding cargo receptor-bound proteins; the vesicle is then pinched off from the ER and transported to the Golgi for packaging.
chromatin
DNA and proteins that help package chromosomes
If the products in a chemical equation include H2O, what specific type of reaction is occuring? Are bonds made or broken in this equation?
Dehydration, bonds are made
Lysosomes are membrane-bound vesicles that arise from
Golgi apparatus.
Polar covalent O-H bonds in water molecules enable hydrogen bonds to form between water molecules. Which of the following properties of water result from hydrogen bond formation?
High heat of vaporization, high specific heat, surface tension, adhesion, cohesion
What types of chemical bonds are easily broken in water?
Hydrogen bonds and Ionic bonds
A mutation has developed that has deleted a gene responsible for the formation of vesicles at the trans end of the Golgi apparatus. What effect will this have on the function of lysosomes?
Lysosomes will not form because they arise as vesicles from the trans end of the Golgi apparatus.
lipids: phospholipids
MEMBRANES, polar head and nonpolar tails, composed of 1 glycerol, 1 charged N region, 1 phosphate group (polar head) 2 fatty acids (nonpolar tail), forms a bilayer to avoid water(head toward water, tails away from water)
actin filaments
Microfilaments that are the smallest cytoskeletal filaments but are important in cell shape and strength
When water ionizes it produces
OH- ions and H+
What are the most abundant elements in living things?
Oxygen, carbon, nitrogen, and hydrogen
_______ formed by ______ reactions link amino acids together, forming a linear chain.
Polypeptides, dehydration
intermediate filaments
Tension-bearing fibers that are stable. Keratins provide mechanical strength in skin
Heat of vaporization
The heat energy required to convert 1 mole of a substance from liquid to gas
Specific heat
The heat energy required to raise the temperature of 1 gram of a substance by 1 degree Celsius
Heat capacity
The heat energy required to raise the temperature of an entire object
Heat of fusion
The heat energy that must be released from a substance to convert it from liquid to solid
In a micelle, which portion of the ampipathic molecule is oriented toward the surface of the sphere?
The polar region
When a chemical reaction has reached equilibrium
The rate of the forward reaction is equal to the rate of the reverse reaction
flagella
This is not part of the cytoskeleton. It is a component that facilitates movement of a cell.
intermediate filaments
a strong structural protein that maintains cell shape
Which of the following properties are shared by many chemical reactions that occur in cells? a. They tend toward equilibrium b. They require energy c. They are not reversible d. They require a catalyst
a. They tend toward equilibrium b. They require energy d. They require a catalyst
Bases
absorbs H+ ions
A substance that releases hydrogen ions into solution is called a
acid
Cohesion
aids the movement of fluids through plant vessels
cell theory
all living organisms are made up of one or more cells, cell is the smallest unit of life, cells arise from cells
High heat of vaporization
allows animals to cool themselves through evaporation
Surface tension
allows some insects to walk the surface of water without sinking
Adhesion
allows water to coat the surface of the digestive tract
Functional groups help define the properties of macromolecules. The _____ functional group(s) is/are found within amino acids, while carbohydrates contain the _____ functional group(s).
amino and carboxyl; hydroxyl
basic funtional groups
amino, positive charge, polar, forms part of peptide bonds, amino acids
Electronegativity is the ability of an electron to
attract electrons
Which of the following are common features of chemical reactions? a. Chemical reactions cease when they reach equilibrium b. Chemical reactions proceed towards equilibrium c. Many chemical reactions that occur in cells require catalysts d. Some chemical reactions require an energy input e. Many chemical reactions in living organisms take place in a watery environment
b. Chemical reactions proceed towards equilibrium c. Many chemical reactions that occur in cells require catalysts d. Some chemical reactions require an energy input e. Many chemical reactions in living organisms take place in a watery environment
Which of the following best describes how a hydrogen bond forms? a. Hydrogen and oxygen share electrons when each is present on polar molecules b. Partially + and - charged atoms in two polar molecules are attracted by electrostatic interactions c. Hydrogen forms a covalent bond with another atom and shares its electrons unequally
b. Partially + and - charged atoms in two polar molecules are attracted by electrostatic interactions
Which of the following statements is true of a polar covalent bond? a. The two atoms have similar electronegativity values b. The shared electrons are closer to one nucleus than the other c. Electrons are shared equally between the two atoms d. One or more electrons is transferred from one atom to the other
b. The shared electrons are closer to one nucleus than the other
Which of the following statements describe hydrophilic molecules? a. They contain many nonpolar covalent bonds b. They are soluble in water c. They are smaller than hydrophobic molecules d. They are uncharged
b. They are soluble in water
Ionic bond
bond between an anion and cation
Hydrogen bond
bond between atoms with partial positive and partial negative charges
Nonpolar covalent bond
bond in which two atoms share electrons equally
Polar covalent bond
bond in which two atoms share electrons unequally
Hydrogen bond
bonds between charged molecules or portions of a molecule; weak attraction between slightly charged parts of molecules, which are readily broken and reformed; bonds between water molecules
Hydrolysis reactions
break apart molecules via water
lysosomes
break down macromolecules, contain acid hydrolase- hydrolytic enzyme causes hydrolysis, functions in acidic environment, works on carbs, proteins, lipids, and nucleic acids, autophagy, R1-R2+H2O acid hydrolase->R1-OH+R2-H
catabolism
breaking down molecules or macromolecules in the cell
autophagy
breaking down molecules to components and recycle
transfer RNA (tRNA)
brings in individual amino acids to ribosome
acidic functional groups
carboxyl, phosphate, and sulfate, negative charge, acetic acid, DNA
protein function
catalysis, support, defense, transport, motion, regulation, and storage
Chemical reactions require a source of energy but may still require a(n) __________. Most chemical reactions proceed towards __________.
catalyst, equilibrium
peroxisomes
catalyze reactions that break molecules down by detoxification (adding oxygen); by product: hydrogen peroxide H2O2 of many chemical reactions, catalase in peroxisomes breaks hydrogen peroixe down to make water and oxygen gas
microtubules functions
cell shape, organization of cell organelles, chromosome sorting in cell division, intracellular movement of cargo; cell motility -> motor proteins and microtubules
mitochondria
cellular respiration-> ATP production, outer and inner membrane, cristae, mitochondrial matrix
polysaccharide
cellulose, starch, glycogen
binary fission
chloroplasts and mitochondria divide via binary fission, contain their own circular chromosome mitochondrial and chloroplast genome
microtubules
chromosome sorting during mitosis
microtubules
cilia and flagella; long, hollow, and cylindrical; made of tubulin subunits, have a plus and minus end, minus end may be anchored, dynamic instability (changing) to alter (grow, add, or shorten subunits)
While hydrogen bonds are constantly breaking and reforming a large percentage of the hydrogen bonds between water molecules exist at all times.
cohesive force
functional groups
commonly occurring groups of atoms in specific formation and specific characteristics
The amount of solute in grams dissolved in a given volume of a solution is the solution's
concentration
Two or more molecules combining to form a larger molecule with a loss of water is known as a ______ reaction
condensation/dehydration
endomembrane system
consists of the nucleus, ER, golgi apparatus, lysosomes, vacuoles, peroxisome, vesicles
lipids
contain a high proportion of nonpolar hydrocarbon bonds which causes them to be hydrophobic and not water soluble, energy storage 3 main types: fats-triacylglycerols, phospholipids, steroids
organic molecules
contain carbon, make up living organisms
Hydrophobic molecules
contain many nonpolar covalent bonds, dissolve well in nonpolar solvents, are not soluble in water
structural isomers
contain some atoms but have a different bonding relationship
nucleus
contains DNA, contains a nucleolus
messenger RNA (mRNA)
contains info for making polypeptide from amino acids
the addition of acid
decreases pH
phagocytic vacuoles in protists and WBCs
degrade molecules via digestive enzymes
Water is formed when two molecules come together to form a large molecule.
dehydration reaction
cell structure
determined by 4 factors: matter, energy, organization, and information
lysosomes
digest worn out organelles and cell debris; digest material taken up by endocytosis
hydrophillic
dissolve in H2O, polar, charged molecules
Hydrophobic molecules usually
dissolve well in nonpolar solvents, are not soluble in water, contain many nonpolar covalent bonds
nuclear envelope
double membrane-outer membrane continuous with ER membrane
DNA
double stranded, housed within the nucleus of an animal cell, nitrogenous bases ATGC
Ionic bond
electrons are transferred between two atoms creating positively and negatively charged atoms, which are then attracted to one another, salt
flagella/cilia
eminate from basal body; anchor, central structure = axenome- 9+2 arrangement, ring of 9 pairs of microtubules and 2 single center microtubules
essential amino acids
essential for function but we cannot produce
The temperature of water rises slowly due to its high specific heat; requiring a lot of energy to convert liquid water to water vapor.
evaporative cooling
cytoplasm
everything within plasma membrane
contractile vacuoles in protists
expel excess water as a form of locomotion
cisternae
fluid filled tubes in ER
cristae
folds formed in inner membrane ->increase surface area for cellular respiration
vacuoles
functions vary with organism and environment
monosaccharide
glucose, fructose, c6h12o6
golgi processses
glycosylation continued from ER, protease cuts proteins/large polypeptides into smaller [proteolysis-breaking up proteins], secretion through secretory pathway to material from golgi packed into secretory vesicles and transported to other locations and plasma membrane
An ampipathic molecule
has polar and nonpolar regions
ampipathic
has polar and nonpolar regions
eukaryotic cells
have membrane bound organelles, same components, different morphologies in different types of cells, serve different purposes, form fits function, compartmentalization
polysaccharides
hundreds of thousands of monosaccharides linked, energy storage starch and glycogen, structural cellulose, support chitin
A base will absorb _______ ions in solution
hydrogen
In the secondary structure of a protein, what bonds, other than peptide bonds, are formed?
hydrogen bonds
The addition of water can break apart molecules into two smaller molecules.
hydrolysis
When H2O is added to a compound in a chemical equation, a new compound can be formed via what type of reaction?
hydrolysis
The lysosome contains ________ enzymes.
hydrolytic
The plasma membrane is made up of a phospholipid bilayer, with the _____________ of the phospholipids_____________.
hydrophilic heads; sticking out toward the interior and exterior of the cell
In the stable form of protein, what is generally oriented to the interior of the protein molecule?
hydrophobic portions
polar functional groups
hydroxyl, carbonyl, ketone, and aldehyde: hydrophilic, dissolve in h20, alcohols
Water is less dense at 0°C compared to 4°C.
ice floats
stereoisomers
identical boding, but different position of atoms: cis and trans isomers-different in position around double bond; entantiomer-mirror images
intermediate filaments
in many animal species- rope like, made of different protein subunits, keratin, desmin, cumin, cell shape, provide cells with mechanical strength, anchorage of cells and nuclear membrane
the addition of a base
increases pH
Electronegativity differences between atoms dictate the polarity of molecules by
influencing whether covalent bonds are polar or nonpolar
nuclear pores
inner and outer member connect and allow passage of molecules
nucleus
instructions for protein synthesis and cell reproduction; contains genetic information
motor proteins
interact with microtubules or actin filaments for movement; use ATP, move cargo via motor proteins, move and bend filaments
endoplasmic reticulum
intracellular compartment forms transport vesicles; participates in lipid synthesis and synthesis of membrane or secreted proteins
disaccharide
lactose, sucrose, maltose, c12h22o11
macromolecules
large complex organic molecules
condensation/dehydration reactions
links monomers to make polymers or link polymers to maker larger polymers; water is a product
phosphodiester bonds
links sugar to phosphate of other nucleotide a->t c->g
steroids
lipid characterized by a carbon skeleton containing four fused rings, vary by the functional groups added to those four fused rings, include cholesterol and many hormones
What are the four classes of biological molecules?
lipids, carbohydrates, proteins, and nucleic acids
unsaturated fatty acid
liquid at room temperature; oil; found primarily in plants and plant products; double bonds with carbon backbone; trans fats are a synthetic for that has a higher melting point
nucleolus
location of the assembly of ribosomes
Alkaline solutions have the ________ proton concentration. Acidic solutions have the ______ proton concentration.
lowest, highest
Due to hydrogen bonding, water tends to adhere to surfaces, such as the lining of the digestive tract.
lubricant
Cotranslational sorting occurs when
mRNA to proteins occurs in the endoplasmic reticulum and then moves to other organelles.
disaccharides
made by a dehydration reaction, covalently bonded, sucrose, lactose, maltose
nucleotides
made up of a pentose sugar, nitrogenous base, and phosphate group
central vacuoles in plants
maintain turgor pressure(pressure on cell wall that maintain structure of plant cells and plant, helps drive expansion of cell wall) store water, waste, lipids, pigments, and proteins
When mixed with water, ampipathic molecules may aggregate into spheres called
micelles
centrosome
microtubule organization center
semiautonomous organelles
mitochondria, choloroplasts, can self replicate (contain their own DNA), but still require some things from other organelles to function, take up molecules from cytosol
endoplasmic reticulum (ER)
network of membranes form fluid filled tubes =cisternae
saturated fatty acid
no double bonds with carbon backbone; solid at room temperature; comes primarily from animals and animal products
saturated fats
no double bonds, solid at room temperature, all bond positions occupied by H
smooth ER
no ribosomes, contains enzymes that: detoxify [convert hydrophobes to hydrophilles], calcium balance by calcium pumps, synthesize and modify lipids, carbohydrate metabolism
methyl
nonpolar functional group, hydrophobic, may be attached to DNA, carbohydrates and proteins
nuclear matrix
nuclear lamina and membrane organize chromosomes
unsaturated
one or more double bonds, liquid at room temp
proteins
one or more polypeptides folded into specific 3-d structure
golgi apparatus
packages proteins for export from cell; forms secretory vesicle
centrioles
pair of structures within centrosome
What type of bonds link individual amino acids together?
peptide bonds
The correct structure of DNA nucleotides can be presented as
phosphate-sugar-base.
The unequal sharing of electrons between the oxygen and hydrogen atoms within a water molecule makes water a ____ molecule
polar
polypeptides
polymers of amino acids linked by a peptide bond [condensation/dehydration]
nucleic acids
polymers of nucleotides, DNA stores hereditary info, RNA expresses it
the _______ of a protein is the sequence of amino acids that are attached together by _________ bonds
primary structure, peptide
In a dehydration reaction, water is a
product
nucleus functions
protect, organize, and replicate genetic information; assembly of ribosomes***(make protein)
Ribosomes are the site of
protein synthesis
cytoskeleton
provides cell shape, organization, and movement; network of 2 protein filament types: microtubules, intermediate filaments, microfilaments/actin filaments, made of multiple protein monomers
DNA _______. RNA, on the other hand, ________.
provides the instructions for the specific sequence of amino acids used to build a protein; functions to convert a nucleotide sequence into an amino acid sequence
The ________ of a protein exists if multiple polypeptides bind together to form a functional protein
quarternary structure
vacuole
regulates water levels in plant cells
Acids
release H+ ions into solution
hydrophobic
repel H2O, nonpolar molecules, lipids
In the _________ of a protein the polypeptide is folded through the mechanism of amino acids rotating around bonds and folding into a alpha-helix or beta-pleated sheet structure and stabilized by __________ bonds
secondary structure, hydrogen
plasma membrane
semi-permeable boundary between intra and extracellular environment; functions: transport of components in and out of cell, cell signaling -> receptors, cell adhesion -> protein-protein interactions between adjacent cells
cytosol
semifluid matrix, contains sugars, salts, and amino acids
plasma membrane
separates contents of cell from surroundings, made up of phospholipid bilayer
Prokaryotic cells
simple structure, plasma membrane: phospholipid bilayer; cytoplasm; nucleoid region, ribosomes, no membrane bound organelles, structures outside of plasma membrane, cell wall, glycocalyx, appendages
RNA
single stranded, ribose sugar within backbone, nitrogenous bases AUGC
inner membrane of mitochondria
site of ATP synthesis
ribosomes
site of polypeptide synthesis via translation, info within a gene ultimately translated into a sequence of amino acids in a polypeptide, located in various regions of cell, including on ER, made in nucleolus, bring mRNA and tRNA together
chloroplasts
sites of photosynthesis
actin/micro filaments
smallest subunits, made of actin monomers, has positive and negative end, twisted, rope like(strong), cell shape, cell strength, intracellular movement of cargo, cell movement (amoeboid movement), cytokinesis in animal cells(end result of cell division)
A liquid that can dissolve substances is known as a
solvent
The charged ends of a water molecule allow it to surround a solute in solution.
solvent
As a result of the electron configuration of a water molecule, water is a great ______ because water can break up and surround a _______, as long as it is not ______, dissolving it into solution.
solvent; solute; nonpolar
ER lumen
space inside each cisterna
mitochondrial matrix
space within inner membrane
golgi apparatus
stack of flattened, membrane bounded compartments, relative to ER location cis(closest), medial, trans (farthest), vesicles transport materials between stacks, secretion, processing, protein sorting, post office of cell
Covalent bonds
strong chemical bond due to the sharing of electrons, bonds between hydrogen and oxygen atoms in a water molecule
actin
structural protein used to move cells, structural protein used in muscle contraction
rough ER
studded with ribosomes, protein sorting, inserting proteins into ER membrane and modifying carbohydrates by adding a protein or lipid to it(glycosylation)
thiol functional groups
sulfhydrl, have sulfur, form disulfide bridges, some amino acids
metabolism
sum of all biochemical reactions within a cell
cytosol
surround organelles in plasma membrane, 20-50% of cell volume, central hub for many metabolic activities
anabolism
sythesizing molecules and macromolecules in the cells
adhesion
tendency for molecules to stick to other molecules
cohesion
tendency for molecules to stick to themselves
In the ________ of a protein the amino acid side chains of the folded polypeptide interact, forming a complex __________
tertiary structure, 3-dimensional shape