Biology Exam Ii

Front 1

Photomorphogenesis

Back 1

light regulation of plant development

Front 2

What 4 things do plants detect?

Back 2

light prescence, wavelenths, intensity, and duraton of light

Front 3

What are the 2 major classes of light receptors

Back 3

blue light receptors
Phytochromes

Front 4

What does blue light regulate?

Back 4

stomatal opening
phototrophism
light induced slowing of hypocotyl elongation

Front 5

Photochrome

Back 5

Pigment that absorbs light in the red:far red range

-absoroption of light in these ranges changes the conformation state of the phytochrome molecule

Front 6

Pr v. Pfr
-which is most reactive?
-what are their wavelengths?

Back 6

Pfr more reactive
Pr - 660 nm
Pfr- 730 nm

Front 7

What does Photochrome control?

Back 7

seed germination
perception of shade
perception of day length(recognize the lenght of dark)

Front 8

Photoperiod

Back 8

the relative length of night and day, plants use phytochrome to measure the photoperiod

Front 9

Short Day Plants

Back 9

Require long nights and a flash of red light that interrupts the night prevents flowering (High Pr causes flowering)

Front 10

Long Day Plants

Back 10

Require short nights in order to flower, flash of red light that interrupts the night stimulates flowering (high Pfr causes flowering, high Pf inhibits flowering)

Front 11

Circadian Rhythm
-define
-associated with what?

Back 11

endogenously controlled cycles that occur on a roughly 24 hour cycle
-reinforced by phytochrome

Front 12

Electrical Signaling

Back 12

rapid, long distance electrical signally thru the phloem, stimulus can trigger an electrical signal in the phloem that affects another part, such as elicting a change in gene transcription, repsiration, photosynthesis...phloem can serve a nerve like function

Front 13

Where in plants does mitotic divisions occur?

Back 13

in meristems

Front 14

G1
S
G2

Back 14

G1: chromosomes unfold, organelles multiply, membranes are synthesized
S: unfolded chromosomes are replicated
G2: preparation for cell division

Front 15

Mitosis

Back 15

division of the nucleus

Front 16

Centromere

Back 16

Specialized region of the chromosome where the sister chromatids are attached.

Front 17

Ploidy

Back 17

the number of unique sets of complete chromosomes

Front 18

Somatic Cells

Back 18

diploid, two complete sets of chromosomes, they are not gametes

Front 19

Name the 3 domains of life.

Back 19

1. Bacteria
2. Archaea
3. Eukarya

Front 20

Phylogenetic Hypothesis

Back 20

a description of the evolutionary history of relationships among organsims

Front 21

Taxon

Back 21

any group of species that we name

Front 22

Clade

Back 22

A group of species that includes an ancestral species and all its descendants

Front 23

Node or Split

Back 23

the point of divergence betweeen lineages, a hypothetical most recent ancestor

Front 24

Example of a DERIVED TRAIT

Back 24

seeds are a derived trait meaning they are different from ancestor

Front 25

6 forms of green algae

Back 25

colonial
unicellular
filamentous
plate-like
sheet-like
coenobial=super cell

Front 26

3 characteristics that all green algae has in common are...

Back 26

1. chlorophyll a and b
2. starch as a storage product
3. cellulose in their cell walls

Front 27

Chlamydomanas

Back 27

"the lab rat", reproduce both sexually and asexually, environmental stress such as nitrogen shortage trigger meiosis (sexual reproduction)

Front 28

Charophytes

Back 28

the closest living relatives of land plants (embryophytes)

Front 29

4 Shared derivates of charopytes and embryophytes

Back 29

1. rosette-shaped cellulose synthase complexes
2. Perioxisomes that contain enzymes that minimize loss of carbon during photorespiration
3. formation of phragmoplasts
4. a particular structure of flagella

Front 30

Aquatic v. terrestrial

Back 30

Aquatic: medium is supportive, water available, mineral uptake over the surface, CO2 and O2 limiting, light intensity attenuated by H2O

Terrestrial: medium not supportive, range of water availabilty, mineral uptake mostly from soil, CO2 and O2 not limiting, light intensity potentially high

Front 31

Sporopollenin

Back 31

Durable polymer that prevents exposed zygotes from drying out, protection

Front 32

Cooksonia

Back 32

the first land plant 425 mya.
tiny, non-photosynthetic stalked reproductive structures on a flattened photosynthetic thallus

Front 33

Bryophytes

Back 33

land plants that diverged the earliest, non-vascular, has spores, includes liverworts, hornworts, and moses

Front 34

Sphagnum

Back 34

forms peat, type of moss

Front 35

5 Characteristics of all Bryophytes

Back 35

1. small
2. non-vascular
3. no true roots
4. no secondary cell walls of any kind i.e no ligin
5. the leaf plant body is haploid

Front 36

The dominant stage of the life cycle for Bryophytes is...

Back 36

gametophytes

Front 37

Gametophytes

Back 37

produce gametes thru mitosis

Front 38

Antheridia

Back 38

sperm chambers

Front 39

Archegonia

Back 39

Egg chambers

Front 40

Sporophyte

Back 40

the plant that is going to produce spores, 2N, multicellular

Front 41

Sporangium

Back 41

Capsule, special chamber where spores are produced

Front 42

Spores

Back 42

1N

Front 43

Syngamy

Back 43

the fusion of gametes, does not have to occur at the same time as fertilization

Front 44

"Alternation of Generations"

Back 44

alternation in the life cycle between haploid generation and a diploid generation(alternation between gametophytes and sporophytes)

Front 45

Shared Characteristics of Bryophytes:

Back 45

1. alternation of generations with multicellular sporangia and gametangia
2. embryos
3. thin cuticles
4. more sporopollenin on spore walls
5. stomates on sporophytes
6. very simple apical meristems

Front 46

Lycophytes

Back 46

respresent the earliest diverging clade of vascular land plants

Front 47

Pteridophytes

Back 47

ferns, horsetails, whisk ferns are modern representatives of early vascular plants

Front 48

Fern Sori

Back 48

clusters of sporangia on the underside of the fern leaves, starts out diploid and then haploid to undergo meiosis

Front 49

Embryophytes

Back 49

includes bryophytes, lycophytes, pteridophytes, gymnosperms, and angiosperms(everything but charophytes/green algae)

Front 50

Tracheophytes

Back 50

all land plants with vascular tissue, includes lycophytes, pteridophytes, gymnopersm, and angiosperms

Front 51

Gymnosperms

Back 51

a vascular plant that bears naked seeds or seed not enclosed in a special chamber

Front 52

Angiosperms

Back 52

a flowering plant, which froms seeds inside a protective chamber called an ovary

Front 53

What do seeds require?

Back 53

1. further reduction of the gametophyte size
2. Heterospory
3. Retention of the entire haploid phase of the life cycle within tissue produced by the parent

Front 54

Homosporous

Back 54

only one type of spore produces one type of gametophyte(having the same morphology and size and gives rise to one type of gametophyte) that produces both antheridia and archegoinia

Front 55

Heterosporous

Back 55

2 types of spores each produces a different type of gametophyte (microgametophtye and megagametophyte)

Front 56

What does a seed contain?

Back 56

all of the female parts (mega-sporangium, megaspore, megagametophyte, archegonium, eggs)

Front 57

What makes up pollen?

Back 57

all of the male parts (microspore, microgametophyte, sperm)

Front 58

4 Phyla of the gymnosperms

Back 58

1. cycadophyta
2. ginkgophyta
3. gnetophyta
4. coniferophyta

Front 59

Shared Dervied Characeristics of Gymnosperms

Back 59

1. seeds
2. vascualar cambium produces xylem and phloem
3. evolutionary loss of antheridium
4. microgametophytes produced as pollen
5. No dependence on water for fertiliztion

--Gymnosperms do not produce fruit

Front 60

Ovule

Back 60

Megasporangium surrounded by the integrument
-after fertilization the ovule becomes the seed. The integrement becomes the seed coat.

Front 61

Microsporangia

Back 61

contains many cells that undergo meiosis to give rise to spores

Front 62

Megasporangia

Back 62

a single cell that undergoes meiosis, creates 4 megaspores but 3 abort, the megaspore enlarges thru internal divisions to become a multicellular gametophyte

Front 63

Pollen Tube

Back 63

Cytoplasm of the pollen grain that grow thru the tissue toward the archegonium

Front 64

General Evolutionary Trends in Land Plants

Back 64

1. increase in sporocyte (2N) size and complexity
2. reduced dependence on water for fertilization

Front 65

Archaefructus Sinensis

Back 65

displays a mixture of ancestral (no flower petals) and derived (carpals and stamens) angiosperm features

Front 66

Amborella

Back 66

might be the ancestor of flowering plants
-understory shrub from New Caledonia

Front 67

Why have Angiosperms been so successful?

Back 67

-they have relatively faster growth than gymnosperms
-they have shorter life cycles
-they use animals for targeted pollination and fruit dispersal

Front 68

Flowers and Fruits

Back 68

Devices that plants use to seduce trick, manipulate animals into working for them

Front 69

Wind Pollination

Back 69

abiotic, 20% of plants use wind, flowers tend to be small, not brightly colored, produce large amounts of pollen

Front 70

Bee Pollination

Back 70

biotic, 65% of angiosperms are bee pollinated, flowers have: sweet fragrances, bright colors, nectar guides

Front 71

Moth Polliniation

Back 71

White flowers, less fragrant

Front 72

Butterfly Pollination

Back 72

strong and sweet scents, flowers a range of colors

Front 73

Hummingbird Pollination

Back 73

flowers tend to be red, tubular, sometimes yellow, don't smell, produce large amounts of nectar

Front 74

Fly Pollination

Back 74

color of rotten meat and it smells like it

Front 75

Bat Pollination

Back 75

white flowers often open at night

Front 76

Pollen Grain

Back 76

each pollen grain contains 2 or 3 celled microgametophytes, pollen's roughness helps it to stick to things
-pollen grains land on the stigma, germinate and form pollen tubes that deliver the sperm to the ovule

Front 77

Double Fertilization

Back 77

the union of 2 sperm cells with different nuclei of the female gametophyte
1. one sperm fuses with the egg to form the zygote
2. one sperm fuses with the polar nuclei to from triploid (3N) endosperm

Front 78

Shared Derived Features of Angiosperms

Back 78

-flowers
-ovules contained in ovaries
-loss of archegonia
-double fertilization
-most have vessels

Front 79

Gene

Back 79

a unit of heredity, a member of the genome, a stretch of DNA, located on a chromosome, encodes a product(usually a protein)

Front 80

P

Back 80

parental generation
-creates the fillial generation

Front 81

F1

Back 81

first fillial generation
-(F1=PxP)

Front 82

F2

Back 82

second fillial generation
-F2=F1xF1

Front 83

Character

Back 83

heritable features that vary among individuals ex. flower colors

Front 84

Trait

Back 84

each variant for a character
ex. purple/white flowers

Front 85

Hybidization

Back 85

the matching or crossing of two true breeding varieties that differ in one or more traits

Front 86

Blending Hypothesis

Back 86

crosses between different individuals will produce intermediate offspring

Front 87

Particulate Hypothesis

Back 87

offspring will be identical to one or the other parent, there is no inbetween

Front 88

Dominant

Back 88

a trait that over shadows other traits in crosses

Front 89

Recessive

Back 89

a trait that is obscured in a cross involving a dominant trait

Front 90

Homozygous

Back 90

an organism that has a pair of identical alleles for a character
ex. PP

Front 91

Allele

Back 91

one or more variant forms of a gene that produces different traits
ex. purple or white flowers

Front 92

Locus

Back 92

the physical location of a gene on a chromosome

Front 93

Genotype

Back 93

the genetic makeup of an organism, w/ respect to the character(s) of interest ex. Pp

Front 94

Phenotype

Back 94

what we can observe e.g plants with purple flowers

Front 95

Complete Dominance

Back 95

the gene product of one allele entirely masks that of the other allele or the recessive allele makes no functional gene product

Front 96

The Law of Segregation

Back 96

two alleles separate (segregate) during meiosis and end up in different gametes

Front 97

Punnett Square

Back 97

tool to determine the odds of producing different kinds of offspring

Front 98

Test Cross

Back 98

breeding an organism of an unknown genotype with a recessive homozygote, it can reveal the genotype of that organism

Front 99

Law of Independent Assortment

Back 99

Mendel's second law, alleles from two or more different alleles are transmitted independently to gametes (only applies to genes located on different chromosomes)

Front 100

Additive

Back 100

probability of one OR the other event, two OR more ways to get the same event

Front 101

Multiplication

Back 101

probability of two or more events happening (one event AND the other)

Front 102

Incomplete Dominance

Back 102

both alleles contribute to the heterzygous phenotype, neither is completely dominant

Front 103

Codominance

Back 103

alleles produce separate distinguishable phenotypes and both are dominant over recessive alleles (e.g ABO blood type)

Front 104

Pleiotrophy

Back 104

some genes have many different types of effects on the phenotype of an organism

Front 105

Epistasis

Back 105

some genes affect the expression of other genes ex. mouse coat color

Front 106

Multigene traits

Back 106

lots of phenotypes are affected by multiple genes, not all or nothing

ex. human skin color

Front 107

Quantitative Characters

Back 107

many characters vary along a continuum , usually indicative of polygenic inheritance

Front 108

Genetic Linkage

Back 108

genes located on the same chromosome (especially near eachother) are said to be more linked, more often than not alleles of linked genes will be inherited together

Front 109

The Chromosome Theory of Inheritance

Back 109

states that genes are located on chromosomes and that the behavior of chromosomes during meiosis accounts for inheritance patterns

Front 110

Sex Linkage

Back 110

sex-linked genes are located on one of the sex chromosomes

Front 111

Crossing Over/recombination

Back 111

genes that are linked occasionally have different allele combinations than those found in the parental generation, happens during prophase I,

Front 112

Recombination Frequency

Back 112

frequency of recombinant alleles, most easily determined by a test cross, genes located farther away from eachother are more likely to recombine