Biology Exam Ii

Front 1

gene linkage?

Back 1

genes for two separate traits appear on same chromosome

Front 2

gene on which chromsome governs growth of testes?

Back 2

Y chromosome

Front 3

sex linkage?

Back 3

unique situation with X and Y chromosome in male sex cell: only one recessive gene can get expressed... son receives x chromosome from mother and can only pass it to daughters... thus it skips generation

Front 4

examples of sex-linked diseases?

Back 4

red-green colorblind, hemophilia, duchenne muscle dystrophy

Front 5

duchenne muscle dystrophy (DMD)?

Back 5

progressive weakening of muscles, leads to chairriddenness and eventual death by 20's, incurable, gene located on x chromosome

Front 6

barr body?

Back 6

every extra x-chromosome produces this in nucleus, a female has one barr body, while a male has none

Front 7

abnormalities caused by sex chromosome number changes?:

Back 7

speck syndrome, down syndrome, turn syndrome, klinefelter syndrome

Front 8

what causes abnormalities in offsprings such as down syndrome and speck syndrome?

Back 8

the fact that parent chromosome number can change

Front 9

all chromosomes other than sex chromosomes are called what?

Back 9

autosomes

Front 10

down syndrome is caused by?

Back 10

an extra x chromosome (trisomy) on the 21st chromosome of the human karyotype

Front 11

prokaryotes have what type of DNA?

Back 11

circular DNA helix

Front 12

eukaryotes have what type of DNA?

Back 12

linear chromosomes

Front 13

double-ringed DNA subunit?

Back 13

adenine, thymine

Front 14

single-ringed DNA subunit?

Back 14

guanine, cytosine

Front 15

DNA subunit pairings?

Back 15

cytosine/guanine, thymine/adenine

Front 16

chromatid?

Back 16

single copy of a chromosome

Front 17

all chromosomes contain ____ ?

Back 17

DNA

Front 18

3 functions of genes?

Back 18

1. code for proteins (structural proteins or enzymes) 2. code for RNA 3. regulating (turns genes "on" or "off")

Front 19

DNA replication?

Back 19

enzyme regulated, new strand is half old, half new

Front 20

transcription?

Back 20

involves assembly of RNA molecule

Front 21

translation

Back 21

a certain type of RNA directs linkage of amino acid to produce a polypeptide chain

Front 22

permanent change in a gene's base sequence

Back 22

mutation

Front 23

alterations in protein structure and protein function are caused by

Back 23

mutations

Front 24

chain of events between DNA and protein

Back 24

DNA is a) transcribed into a messenger RNA which travels outside the nucleus wall and into the cytoplasm where through b) translation turns into a protein

Front 25

difference between RNA and DNA?

Back 25

RNA is single stranded, and the "thymine" subunit is not thymine but "uracil"

Front 26

3 RNA types?

Back 26

messenger(mRNA), transfer (tRNA), ribosomal (rRNA)

Front 27

messenger RNA?

Back 27

complementary copies of DNA sequences formed from only one strand of the DNA, which carries the code from genes to ribosomes

Front 28

transfer RNA?

Back 28

carries amino acids to ribosome (with Anticodon)

Front 29

ribosomal RNA?

Back 29

combines with protein to form ribosomes, on which protein synthesis occurs

Front 30

translation of RNA... elaborate

Back 30

occurs on the endoplasmic reticulum (rough ER), messenger RNA codons are used to specify amino acids, ribosomes read messenger RNA codons to synthesize a specific sequence of amino acids, each different amino acid has a unique carrier transfer RNA that brings acids to the ribosome

Front 31

initiation codon?

Back 31

(AUG), tells ribosomes to begin synthesis of protein

Front 32

stop codons?

Back 32

(UAA), (UAG), (UGA)

Front 33

genetic code words read in triplets or

Back 33

codons

Front 34

what is produced when codons are read in triplets?

Back 34

amino acids

Front 35

exons

Back 35

coding sequences of DNA

Front 36

introns

Back 36

one type of non-coding sequences of DNA (in eukaryotes, more than 90% are non-coding)

Front 37

which species use codons?

Back 37

all eukaryotes, codon is basically universal. all living things share codons: genetic engineering, common ancestors

Front 38

a mature mRNA transcript consists of?

Back 38

encapsulated introns that get "snipped" out after a half-DNA transcript is separated from the base

Front 39

how many types of mRNA codons are there?

Back 39

64

Front 40

how many types of possible amino acids are there?

Back 40

20

Front 41

3 steps of translation?

Back 41

1. initiation 0 tRNA and mRNA are loaded onto a ribosome, 2. elongation - polypeptide chain forms as mRNA passes through rough ER and is translated, stop codon and detachment of mRNA and popypeptide chain results in - 3. termination

Front 42

how is protein synthesized (generally)?

Back 42

mRNa forms a large and small subunit which are conjoined, two sites in the large subunit "read" the polypeptide chain/tRNA strand, site 'P' binds tRNA carrying the polypeptide, site 'A' binds tRNA carrying the next amino acid

Front 43

termination phase of protein synthesis (translation)?

Back 43

site 'A' in the large subunit of the mRNA reads a "release factor" which is a stop codon instructing it to end the polypeptide chain that is being created. the large and small mRNA subunit then drift away

Front 44

protein synthesis can be affected by ____?

Back 44

gene mutations

Front 45

pointed gene mutation?

Back 45

mutation limited to one or few base pairs on single gene

Front 46

2 types of pointed gene mutation?

Back 46

1. substitution 2. insertion/deletion

Front 47

purpose of gene mutation such as substition?

Back 47

makes small but significant change in the protein, which leads to genetic diversity... "good" substitutions with help with evolution and survival of descendants

Front 48

types of gene substitution?

Back 48

1. missense 2. nonsense 3. conservative 4. silent

Front 49

nonsense/missense mutations create what kind of proteins?

Back 49

typically nonfunctional proteins, with missense possibly leading to disease like sickle cell, nonsense leads to truncated, nonfunctional protein due to a premature stop codon

Front 50

silent mutation?

Back 50

changes that do not affect final protein, either because they are in an intron or an exon in a manner that doesn't affect final amino acid sequence

Front 51

conservative mutation?

Back 51

subtle change in DNA sequence that still creates the same amino acid... but is still a change

Front 52

lamarck's theory?

Back 52

that species "improve" over time, used neck of giraffe as an example, believed that environment was an important factor

Front 53

darwin's evidence for evolutionary theory came from?

Back 53

geological evidence & fossils, theories about population growth, his observations of living organisms

Front 54

evolutionary evidence showed distinct yet similar organism fossil records in species that were (3 things)

Back 54

1. in similar climates 2. isolated populations of same species 3. island vs. mainland population

Front 55

what about population studies interested darwin?

Back 55

many offspring were produced, very few survived to reproduce

Front 56

darwin's example of natural selection?

Back 56

finches. when they moved from mainland to the islands, they underwent adaptive radiation and changed into several very similar but distinct species, each suited to the environment

Front 57

speciation occurs as a result of

Back 57

mutation, genetic drift, natural selection

Front 58

radiocarbon dating method?

Back 58

depends on ratio of radioactive carbon (C14) to stable carbon (C12)

Front 59

what type of carbon decays, circumstances?

Back 59

C14, once living thing dies

Front 60

homology

Back 60

similarities in species caused by common ancestor

Front 61

analogy

Back 61

similarities in species caused by similar environment

Front 62

axes of evolutionary trees?

Back 62

vertical is time, horizontal is pattern of relationships

Front 63

buildup of allele frequencies between populations?

Back 63

genetic divergence

Front 64

urey and miller theory of spontaneous creation of life

Back 64

UV light/electrical discharge caused reactions between methane, ammonia and other gases to produce small organic compounds (amino acids)

Front 65

experimented to try and create life in conditions similar to primordial earth?

Back 65

stanley miller

Front 66

3.9-2.5 billion years ago... this era is called and characterized as what?

Back 66

archaen era... first oxygen producing cells develop as anaerobic bacterium

Front 67

first eukaryotes appear in... era

Back 67

proterozoic

Front 68

endosymbiotic theory?

Back 68

holds that chloroplasts and mitochondria are descendants of once free-living prokaryotic organisms that were engulfed by eukaryotes and evolved into permanent symbionts

Front 69

era characterized by terrestialization of species, including plants and vertebrates

Back 69

paleozoic era

Front 70

age of reptiles

Back 70

mesozoic era

Front 71

end of mesozoic period?

Back 71

cretaceous period - flowers and birds evolve further, dinoasurs are extincted

Front 72

era that lead to rise of men?

Back 72

cenozoic era

Front 73

first 3 adaptions which allowed small mammals to fluorish in cenozoic era?

Back 73

limb arrangement --> quicker movement, lower jaw/teeth changes --> wider diet, septum/4-chambered heart --> higher respiration rate

Front 74

second 3 adapations which allowed small mammals to fluorish in cenozoic era?

Back 74

endothermy --> warm-bloodedness, reproductive changes --> internal development of fetus, mammary glands, convergent evolution --> similar structures with similar functions evolved in different places

Front 75

arboreal primate-like structures in human beings?

Back 75

flexible limbs and spine, hands and feet that grasp objects, opposable thumbs, omnivorous diet, complex brain

Front 76

two subgroups of primates?

Back 76

prosimians like lemurs and tarisians (earlier primates) and arthropoids (apes, chimps, humans) which developed later

Front 77

behavioral differences between arthropoid and prosimians?

Back 77

diurnal (active during day), enhanced color vision, live in complex social groups, care for young for prolonged periods

Front 78

two critical steps in arthropoid development towards human beings?

Back 78

bipedal and enlargment of brain relative to rest of body

Front 79

first "human" arthropoids? characteristics?

Back 79

homo habilis - tree climber, bipedal, larger brains, used tools, more diverse diet including soft fruits and insects, nuts

Front 80

primate group that comes after homo habilis?

Back 80

homo erectus - walked fully upright, bigger brains, hunter-gatherers, use of primitive language

Front 81

came after homo erectus?

Back 81

homo sapien - capable of abstract thought, farming, language, social customs, religion

Front 82

multiregional hypothesis of origin of modern humans?

Back 82

interbreeding between cro-magnon, homo erectus and other hominids?

Front 83

replacement (out of africa) theory of origin of modern humans?

Back 83

homo sapiens originated in africa and spread to the rest of the world, replacing whatever more primative species of human was present

Front 84

evidence supports which theory of modern human origin?

Back 84

replacement theory, genetic divergence time about 100,000 yrs ago, which is consistent. mtDNA extracted from Neanthradal bones falls completely out of range of modern man, making it very unlikely

Front 85

association of organisms and their environment?

Back 85

ecosystem

Front 86

flow of nutrients and energy in ecosystem?

Back 86

nutrients are recycle and energy flows THRU an ecosystem

Front 87

limits amount of trophic levels in an ecosystem

Back 87

energy loss

Front 88

energy is lost at each trophic level through 3 things:

Back 88

heat, growth/reproduction, organism's activities

Front 89

3 types of food pyramids?

Back 89

biomass, number, energy flow

Front 90

pyramids of biomass represent ___?

Back 90

ecological consequence of low trophic efficiencies

Front 91

pyramid that represents how the levels are porportional to the number of individuals present in each trophic level

Back 91

pyramid of numbers

Front 92

dynamics of energy through ecosystems have important implications for human population.... how?

Back 92

humans -> cattle -> corn... energy is wasted as it passes through trophic levels. humans -> corn. more direct, less energy is wasted.

Front 93

initial energy source for almost all ecosystems?

Back 93

sunlight

Front 94

feeding relationships are structured as _________ in ecosystem?

Back 94

trophic levels

Front 95

number of individuals an environment can support?

Back 95

carrying capacity

Front 96

population growth characterized as very rapid and in ideal conditions

Back 96

exponential growth

Front 97

exponential growth is plotted on a graph by what characteristic shape?

Back 97

J-shaped curve (population begins to double faster and faster)

Front 98

a natural population will exhibit a carrying capacity over time and a population graph will be characterized by what shape?

Back 98

S-curve, population begins to wane and cap after carrying capacity is reached

Front 99

limiting factors on growth?

Back 99

food, minerals, water

Front 100

survival-curve shape depends on different factors such as... ?

Back 100

type of population, number of young, sexual or asexual reproduction, level of care for young

Front 101

type of survivorship charts?

Back 101

type I, type II, type III

Front 102

what type of survivorship chart is exhibited by humans?

Back 102

type I (juvenile survival is high and organisms die at older ages)

Front 103

what contributes to growth of a population?

Back 103

immigration (joining the population), emigration (leaving the population)

Front 104

pop. density-independent limiting factors?

Back 104

soil, nutrients, weather, physical features

Front 105

pop. density-dependent limiting factors?

Back 105

competition for resources, accumulation of poisons, disease

Front 106

interaction of ecosystem?

Back 106

individuals of a species form populations living in a certain habitat, several populations interact to form communities, many communities + abiotic factors form an ecosystem

Front 107

organisms vie for the same amount of resources in an environment

Back 107

competition

Front 108

limited resources -> means most efficient of two competing species with eliminate other species in that location

Back 108

competition exclusion

Front 109

when two or more species compete for same amount of resources, they must choose to do this, or use a different niche

Back 109

resource-partition

Front 110

relationship in which one organism kills and eats another as prey

Back 110

predation

Front 111

2 prey adaptations to avoid being food for predators?

Back 111

mimicry of organisms with defenses, camouflage by color adaptation

Front 112

when an organism from one species benefits from its interactions with another and the other species neither benefits nor is harmed

Back 112

commensalism (clownfish and anenomes)

Front 113

relationship between species where they live together in close association and there are benefits for both

Back 113

mutualism

Front 114

relationship in which one organism lives off the host, and the host is usually harmed

Back 114

parasitism (bacteria, fungi)

Front 115

process of environmental change where a sequence of communities replaces another over time

Back 115

succession

Front 116

two types of succession and description

Back 116

primary succession: in areas not previously supporting organisms (pioneer community)

secondary succession- in areas originally occupied but disturbed by humans or nature

Front 117

a man who carries a harmful sex-linked (on the x-chromosome) gene will pass the gene on to ______ % of which offspring?

Back 117

half of his daughters

Front 118

each person has at most __ alleles?

Back 118

2

Front 119

a man who carries a Y-linked allele will pass it on to _______

Back 119

all of his sons

Front 120

semi-conservative DNA replication means ______

Back 120

each new DNA molecule is half the old one

Front 121

frameshift mutation is another term for?

Back 121

insertion/deletion mutation

Front 122

which disease is a male with Barr body in each of his body cell?

Back 122

klinefelter's syndrome

Front 123

if a woman carries an x-linked recessive trait, the probability that her son will have it is ____ %

Back 123

100%

Front 124

double-ring bases connect to _______-ring bases

Back 124

single

Front 125

if a bacterial protein has 60 amino acids, how many nucleotides are needed to code for it?

Back 125

180

Front 126

darwin and ______ both proposed similar theory of natural selection

Back 126

wallace

Front 127

organisms originally responsible for putting oxygen in our atmosphere?

Back 127

cyanobacteria

Front 128

what allowed mammals to diversify?

Back 128

dinosaur extinction

Front 129

in addition to Homo, another genus within hominid family is ______

Back 129

australpithecus