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184 Cards in this Set

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Alpha helix
A spiral shape constituting one form of the secondary structure of proteins, arising from a specific hydrogen-bonding structure.
amino acid
An organic molecule possessing both carboxyl and amino groups. Amino acids serve as the monomers of proteins.
beta pleated sheet
One form of the secondary structure of proteins in which the polypeptide chain folds back and forth, or where two regions of the chain lie parallel to each other and are held together by hydrogen bonds.

A sugar (monosaccharide) or one of its dimers (disaccharides) or polymers (polysaccharides).

A structural polysaccharide of cell walls, consisting of glucose monomers joined by b-1, 4-glycosidic linkages.
Protein molecules that assist the proper folding of other proteins.

A structural polysaccharide of an amino sugar found in many fungi and in the exoskeletons of all arthropods.

A steroid that forms an essential component of animal cell membranes and acts as a precursor molecule for the synthesis of other biologically important steroids.
condensation reaction
condensation reaction

A reaction in which two molecules become covalently bonded to each other through the loss of a small molecule, usually water; also called dehydration reaction.
dehydration reaction
dehydration reaction

A chemical reaction in which two molecules covalently bond to each other with the removal of a water molecule.
For proteins, a process in which a protein unravels and loses its native conformation, thereby becoming biologically inactive. For DNA, the separation of the two strands of the double helix. Denaturation occurs under extreme conditions of pH, salt concentration, and temperature.
deoxyribonucleic acid (DNA)
A double-stranded, helical nucleic acid molecule capable of replicating and determining the inherited structure of a cell's proteins.

The sugar component of DNA, having one less hydroxyl group than ribose, the sugar component of RNA.
A double sugar, consisting of two monosaccharides joined by dehydration synthesis.
disulfide bridge
Strong covalent bonds formed when the sulfur of one cysteine monomer bonds to the sulfur of another cysteine monomer.
double helix
double helix

The form of native DNA, referring to its two adjacent polynucleotide strands wound into a spiral shape.
A biological compound consisting of three fatty acids linked to one glycerol molecule.
fatty acid
fatty acid

A long carbon chain carboxylic acid. Fatty acids vary in length and in the number and location of double bonds; three fatty acids linked to a glycerol molecule form fat.
A discrete unit of hereditary information consisting of a specific nucleotide sequence in DNA (or RNA, in some viruses).
An extensively branched glucose storage polysaccharide found in the liver and muscle of animals; the animal equivalent of starch.
glycosidic linkage
A covalent bond formed between two monosaccharides by a dehydration reaction.

A chemical process that lyses, or splits, molecules by the addition of water; an essential process in digestion.
hydrophobic interactions
hydrophobic interaction

A type of weak chemical bond formed when molecules that do not mix with water coalesce to exclude the water.

One of a family of compounds, including fats, phospholipids, and steroids, that are insoluble in water.
A giant molecule formed by the joining of smaller molecules, usually by a condensation reaction. Polysaccharides, proteins, and nucleic acids are macromolecules.
The subunit that serves as the building block of a polymer.

The simplest carbohydrate, active alone or serving as a monomer for disaccharides and polysaccharides. Also known as simple sugars, the molecular formulas of monosaccharides are generally some multiple of CH2O.
nucleic acid
A polymer (polynucleotide) consisting of many nucleotide monomers; serves as a blueprint for proteins and, through the actions of proteins, for all cellular activities. The two types are DNA and RNA.
The building block of a nucleic acid, consisting of a five-carbon sugar covalently bonded to a nitrogenous base and a phosphate group.
peptide bond
The covalent bond between two amino acid units, formed by a dehydration reaction.
A molecule that is a constituent of the inner bilayer of biological membranes, having a polar, hydrophilic head and a nonpolar, hydrophobic tail.
A long molecule consisting of many similar or identical monomers linked together.
A polymer consisting of many nucleotide monomers; serves as a blueprint for proteins and, through the actions of proteins, for all cellular activities. The two types are DNA and RNA.
A polymer (chain) of many amino acids linked together by peptide bonds.
A polymer of up to over a thousand monosaccharides, formed by dehydration reactions.
primary structure
The level of protein structure referring to the specific sequence of amino acids

A three-dimensional biological polymer constructed from a set of 20 different monomers called amino acids.

One of two families of nitrogenous bases found in nucleotides. Adenine (A) and guanine (G) are purines.
One of two families of nitrogenous bases found in nucleotides. Cytosine (C), thymine (T), and uracil (U) are pyrimidines.
quaternary structure
The particular shape of a complex, aggregate protein, defined by the characteristic three-dimensional arrangement of its constituent subunits, each a polypeptide.
ribonucleic acid (RNA)
A type of nucleic acid consisting of nucleotide monomers with a ribose sugar and the nitrogenous bases adenine (A), cytosine (C), guanine (G), and uracil (U); usually single-stranded; functions in protein synthesis and as the genome of some viruses.
The sugar component of RNA.
saturated fatty acid
A fatty acid in which all carbons in the hydrocarbon tail are connected by single bonds, thus maximizing the number of hydrogen atoms that can attach to the carbon skeleton.
secondary structure
The localized, repetitive coiling or folding of the polypeptide backbone of a protein due to hydrogen bond formation between peptide linkages.
A storage polysaccharide in plants consisting entirely of glucose.
A type of lipid characterized by a carbon skeleton consisting of four rings with various functional groups attached.
tertiary structure
Irregular contortions of a protein molecule due to interactions of side chains involved in hydrophobic interactions, ionic bonds, hydrogen bonds, and disulfide bridges.
Three fatty acids linked to one glycerol molecule.
unsaturated fatty acid
A fatty acid possessing one or more double bonds between the carbons in the hydrocarbon tail. Such bonding reduces the number of hydrogen atoms attached to the carbon skeleton.
x-ray crystallography
x-ray crystallography

A technique that depends on the diffraction of an X-ray beam by the individual atoms of a molecule to study the three-dimensional structure of a molecule.
oxygen accumulate in atmosphere
2.7 billion years ago
2.1 billion years ago
multicellular eukaryotes
1.2 billion years ago
500 million
life begins
non living materials became organized into molecular aggregates that eventually could reproduce and metabolize molecules
spontaneous generation
old theory that life arose from non-living matter
theory that life can arise only from the reproduction of preexisting life
4 parts of current theories
1. small organic molecules were synthesized
2. these molecules joined into polymers
3. self replicating molecules emerges
4. all these molecules were packaged into membrane containing droplets whose internal chemistry differed from external environment

simulation of early conditions on earth have produced organic polymers
first genetic material
is RNA and DNA (hypothesized)
aggregates of molecules that were produced abioticly (hypothetical) have a consistent and internal environment have some other properties assosciated with life
5-kingdom system
early 70s, monera, protista, plantae, fungi, animalia
3 domain system
Eubacteria, Archaea, and Eukarya

makes kindom of monera absolete
work in progress, protista now being studied more to
3 most common shaped of prokaryotes
sphere, rods, helixs
most proks have a cell wall that contains peptidoglycans
bacteria have simpler wall that contains more peptidoglycans
cells have walls that are structurally more complex
proks use these appendages to adhere to each other or to surrounding surfaces
over half of proks are motile because they possess whip-like flagella
in addition to their one major chromosome, proks have smaller independent pieces
binary fission
proks method of reproduction
three mechanisms in which proks can transfer genetic material
1. transformation - prok takes up genes from its environment
2. conjugation - genes are directly transferred from one prok to another
3. transduction - viruses transfer genes between proks
major source of genetic variation
4 groups of prokaryotes
1. photoautotrophs photosynthetic and use the power of sun light turn CO2 into organic cmps
2. chemoautotrophs also use carbon dioxide as source of carbon but get energy from oxidizing inorganic substances
3. photoheterotrophs use light to make atp but must obtain their carbon from an outside source already fixed in organic cmps
4. chemoheterotrophs get both carbon and energy from organic compounds, includes most proks
two types of chemoheterotrophs
saprobes - decomposers
nitrogen fixation
process some proks use atmospheric nitrogen as a direct source of nitrogen, convert N2 to NH4+
obligate aerobes
cannot grow without oxygen for cell respiration
obligate anaerobes
use fermentation and are poisoned by oxygen
facultative anaerobes
use oxygen if available or undergo fermentation if not
live in extreme environments such as geysers
3 types of extremophiles
methanogens use carbon dioxide to oxidize H2 and to produce methane as biproduct
2. extreme halophiles- live in salene environments
3. extreme thermophiles live in hot environments
form relationships with other species, one organism is significantly larger and is called host
3 types of symbiosis
mutualism- both benefit
commensalism - one benefits, the other is neither helped nor harmed
parasitism - one benefits one does not
simplest but most diverse of all euks, vary in structure and function more than any other group of euks, most are unicellular and use aerobic metabolism + have mitochondria
animal like protists
plant like protists
most protists
have cilia + flagella, mitosis, aquatic environments
secondary loss of mitochondria

diplomonadida - two separate nuclei - giardia

parabasala - undulating membrane
photosynthetic, heterotrophic, and mixotrophic flagellates

Euglenophyta paramlylon as storage polysacharide \

kinetoplatida kinetoplast, unique organel
subsurface alveoli-membrane bound cavities

1 dinoflaggelata A unicellular photosynthetic alga with two flagella situated in perpendicular grooves in cellulose plates covering the cell.
2. apicomplexa - apical complex functioning in penetration of hosts cells - plasmodium
3. ciliophora - cilia functioning in movement and feeding - paramecium
clade of hairy flagella

oomycota- hyphae which absorb nutrients, water molds, rusts, downy mildews

2. bacillariophyta - diatoms - glassy two part walls

3. chrysophyta (golden algae) biflagellate cells, xanophyll pigments
4. phaeophyta (brown algae) brown color from accessory pigments
rhodophyta (red algae)
no flagellated stages,
viridiplantae (includes green algae group, chlorophyta)
plant-type chloroplasts
decomposers having complex life cycles with amoeboid stages

1. mixogastridia (plasmodial slimemolds) - net like plasmodium as feeding stage
2. dicteostalida (cellular slime molds) amoeboid feeding cells that aggregate to form reproductive colonies
pseudopod equiped protists of uncertain phylogeny
1. rhizopoda - lobe-like pseudopodia - amoeba
2. Actiniopada - ray-like pseudopodia
3. foraminifera - porous cells
four main groups of land plants
bryophytes, pteridophytes, gymnosperms, angiosperms
several adaptations for land living, lack vascular tissues
lack seeds
plant embryos packaged with food supply and protective coat
seeds that are not enclosed in protective coating
flowering plants
alternation of generations
all land plants- have life cycle consisting of two stages, the gametophyte (haploid) and sporophyte (diploid) stage
a cell produced by plants - can develop into new plants without fusing with another cell
3 adaptations enabling plants to live on land
1.vconservation of water, cuticle is a waxy layer made up of polymers that seals water into cell, stomata openings on the undersurface of leaf that open and close to allow evaporition of water and CO2
2. transport of water through body of plant, xylem +phloem
3. adaptation of transport of photosynthesized food, glucose, phloem tubules
three phyla in bryophyta
mosses, liverworts, hornwarts

dominant generation is gametophyte
seedless vascular plant life is dominated by sporophyte stage

ferns and horsetails are prominant examples
seed plants
vascular plants that produce seeds
three most crucial adaptation of plants that lead to evolution of seed plants
1. reduction of gametophyte stage
2. evolution of seed
3. evolution of pollen
microspores of seed plants develop into pollen grains, which are dispersed by the wind or animals, so that this process can take place
prominant gymnospers are conifers (cone bearing plants)
two types of cones of pine trees
pollen cones and ovulate cones
phyla anthophyta,

1. monocots have veins that run parallel
2. dicots have net like vein patterns
-flower is major reproductive adaptation of angiosperms
mature ovaries of the plants
8 steps in angiosperm life cycle
1. anthers produce microspores
2. micropores-also known as pollen, form male gametophyte
3.meanwhile ovules form megaspores that form female gametophytes (embryo sacs)
4. pollination brings gametophytes together in ovary
5. double fertilization takes place
6. zygotes develop into sporophyte embryos packaged into along with food into seeds
mutual evolutionary influence btwn plants and animals
4 ways fungi differ from other euks
1. nutrition, structure, growth, reproduction
fungi are heterotrophs and obtain nutrients by absorption in which they secret hydrolytic enzymes and digest food outside their bodies
bodies of fungi composed of filaments, entwined together to form mycelium
walls between hyphae cells made of chitin
four phyla of fungi
1. chytridiomycota - aquatic sapropes or parasites, most primitive
2. zygomycota - terrestrial, some form mycorrizae, mutual association with roots, bread mold
sac fungi, live in a variety of habitats
club fungus, include muchroms and are important decomposers of plant materials
3 important fungi
1. molds - rapidly growing fungi that produce asexually
2. yeasts - unicellular fungi that live in moist habitats, produce asexually by budding
3. lichens - symbiotic associations of photosynthetic microrganisms (algae) embedded in a network of fungal hyphae, hardy, pioneers on rock and soil surfaces
multicellular eukaryotes that must ingest preformed organic molecules into their bodies (heterotrophs)
how many animal phyla
about 35
radial symetry
any cut through central axis of the organism produce miror images
bilateral symetry
single cut devides into two
concentration of sensory equipment at one end of the organism
flatworms, have no cavities between their digestive tracks and outer wall of body
possess fluid filled body cavity that separates an animals digestive track from outer body wall
during cambrian explosion, first animals possessed hard, minerlized skeletons
1. subkingdom parazoa phylum porifera
sponges are the oldest animals. they are sessile but very sedate have no nerves or muscles
pores in sponges through which water is drawn
pores in sponges through which water flow out
collect particles from waters that pass through them
function in both male and female in reproduction
capable of regrowing lost parts
2. Subkingdom eumetozoa
radially symetrical animals
animals with true tissues, which sponges lack, two phyla of radiata are, cnidarians and ctenophora
exist in polyp and medusa form, have radial symetry, central digestive compartment known as gastrovascular cavity, cnidocytes 9cells that function in defense and the capture of prey), hydras, jellies, and sea anemonies
come jellies, look like medusal cnidarians, most are spherical, possess row of plates formed from fused cilia, used for locamotion
bilaterally symmetrical animals
see below
1. Acoelomates
animals without body cavity see below
phylum platyhelminthes
flat worms, live in water or damp - exist in parasitic and free living form; are flat with dorsal and ventral surfaces; lack organs that specialize for circulation; reproduce asexually;ex. flukes and tapeworms
phylum nemertea
ribbon worms or probiscus worms, have excretory sensory and nervous systum similar to flat worms, complete digestive tract with a closed circulatory system with no heart
2. pseudocoelomates
phylum nematoda
roundworms, found in most aquatic habitats, bodies not segmented, are cylindrical, have exoskeleton called a cutivle, complete digestive tract but no circulatory system, pseudocoelum, reproduce sexualy, sexes are separate in most species
phylum rotifera
inhabit fresh water, specialized organ systems including complete digestive tract, jaws that grind food, and cilia that draw water into mouth, some practise parthenogenesis
3. coelomates
phylum lophophorata
contain a lophophore - a circular fold of the body wall, with ciliated tentacles surrounding the mouth
phylum muluska
soft bodied animals protected with a hard shell, slugs, squids, octopi, possess a muscular foot for movement, visceral mass made of organs and a mantle secretes a shell, most have separate sexes
phylum annelida
worms, segmented internally and externally, live in damp or sea habitats, have a coelum, closed disestive system, brain like central giglia, and a hydrostatic skeleton
phylum arthropoda
segmented animals with hard exoskeleton and jointed appendages, well developed sensory organs, open circulatory system, organs specialize gas exchange, includes crustacea, chelicerates(spiders,
4. deuterostomia
radial cleavage, share common developmental processes
phylum echinodermata
slow moving, radiate from center. Thin skin covering an exoskeleton, a water cascular system, reproduce sexually and can be divided into six classes, sea stars, urchins, sand dollars, sea cucumbers
phylum chordata
includes two sub phylum composed of invertebrates as well as all vertebrates
have a backbone
vertebrates four anatomical features
many occur only in embryonic development
1. a notochord - long flexible rod, appears during embryonic development between digestive tube and dorsal nurve chord
2. Dorsol hollow nerve chord formed from a plate of ectoderm that rolls into hollow tube
3. pharyngeal slits - allow water to enter and exit mouth without going through digestive tract
4. a muscular tail posterior to the anus
two subphyla of invertebrate chordates
urochordata (tunicates) and cephalochordata (lancelates) simpler versions of vertebrates
four things that differentiate vertebrates
neural crest, significant cephalization, a vertebral column, and a closed circulatory system
two extant classes of jawless vertebrates
class myxini (hagfishes) - marine bottom dwelling scavengers, possess no vertebrae and have a skeleton made of cartilage
class cephalaspidomorphi (lampreys) marine and fresh water, cartilagenous pipe surounds notochord, lack skeleton supported jaws
jawed important classes of fishes and amphibs
class chondrichthyes - flexible endoskeletons composed of cartilage, streamline bodies, denser than water, sink if stop swimming, example - sharks and rays
class osteichthyes
bony fishes, most numerous of all vertebrate groups, ossified means boned endoskeleton, covered in scales, and possess a swim bladder.
three main classes of bony fish
ray-finned fish, lobe finned fish, lung-fishes
class amphibia
maintain close ties with water, rely on skin for gas exchange, some have larval stage with a dual aquatic and terestrial life, eggs lack a shell, fertilization is external, can exhibit complex social behavior
clade amniotes
mammals, birds, and, reptiles
amniotic egg
have a shell that retains water and thus can be laid in dry environment
extraembryonic membranes
in amniotic eggs, function in gas exchange, waste storage, and transport of nutrients to embryo
have scales, obtain oxygen through lungs, not skin.
lay eggs on land;
undergo internal fertilization
ancient reptiles
dinosaurs, pterosaurs
modern reptiles
testudine (turtles)
sphenodontia (tuataras)
squamata (lizards, snakes)
crocodilia (crocs and gaters)
lay amniotic eggs and have scales on their legs, both are vaguely reptilian
how are bird's bodies constructed for flight
light, hollow bones
relatively few organs
flightless bird
birds that fly
(birds) maintain a warm, consistent body temp.
in some cases layer of fat insulate birds and help
maintain internal temp.
differences btwn birds and reps
four chambered heart
high rate of metabolism
larger brains
mammals shared characteristics
all possess mammary glands
possess hair
are endothermic
active metabolism
born rather than hatched
all use internal fertilization
proportionally larger brains
teeth of differentiating size
3 groups
monotremes - egg laying mammals ex. are platypus and spiny anteater
marsupials - pouch where embryo develops
placental mammals - long period of pregnacy and complete development in uterus
characteristics of all primates
grasping hands and feet
large brains short jaws
forward-looking eyes
flat nails
well developed parental care
complex social behavior
two subgroups of primates
1. prosimii - lemurs,
2. Anthropoidea - monkeys, apes, and humans
human evolution
increased brain volume
shortening of the jaw
bipedal posture
reduced size difference btwn sexes
and important changes in family structure