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My University Cards > Invasion Of The Land > Flashcards

Invasion Of The Land Flashcards

0
Q

What are the parts of a spiders leg?

A
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1
Q

What are the two main classifications of trees?

A

Gymnosperm (coniferous, seeds lack an outer coat) and angiosperm (flowering plants, seeds encased)

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2
Q

Which type of plants undergo double fertilisation?

A

angio sperms

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3
Q

how does double fertilisation occur?

A

it occurs between the male reproductive organ, (the male gametophyte) and the female reproductive organ (female gametophyte).

video:

https://www.youtube.com/watch?v=bUjVHUf4d1I

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4
Q

name the types of fin control

A

yaw: side to side

Pitch: up and down

Roll: like rolling over

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5
Q

define viviparous

A

Viviparous animals bear live young that have developed inside the mother’s body

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6
Q

what is ecdysis?

A

shedding of the skin

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7
Q

what is narrow sense co-evolution?

A

both partners evolve in response to the other e.g.

mutualism (+/+)

parasite-host or predator-prey (+/-)

competition (-/-)

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8
Q

coevolutionary interactions can be classified as what two types?

A

narrow sense co-evolution and broad sense co-evolution

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9
Q

what is broad sense evolution?

A

only one of the partners evolves in response to the other

commensalism (0/+) (relationships between two organisms where one organism benefits from the other without affecting it.)

by-product (0/-)

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10
Q

what period did the first land plants appear?

A

ordovician 505 million years ago

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11
Q

what period did the first invertebrates appear?

A

700 million years ago, precambian

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12
Q

when did the first fish appear? (what period)

A

505 million years ago, ordovician

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13
Q

what are the pros of leaving water?

A

Benefits of Leaving the water:

Reduced competition

New food sources (all those land plants!)

Reduced predation

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14
Q

name the body parts on this horseshoe crab

A
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15
Q

what is this and what are the approproate labels?

A

book lung

a. blood
b. stigma
c. air
d. interlamella air spaces
e. Lamellae with blood
f. chamber

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16
Q

Winged insects appeared in the

A

Carboniferous period (starting 360 MYA)

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17
Q

what period was the evolution of the first land tetrapods from lobe-fined fish

A

(end of the Devonian period)

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18
Q

Development of Gymnosperms

associated with

A

Loss in diversity of

Locopds, Horsetails, Ferns

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19
Q

what are Xerophytes

A

they have sunken stomata

cactus

waxy stem, few/no leaves

specialist roots

homiohydric

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20
Q

what is homiohydric?

A

Plants able to regulate water loss and to remain hydrated for some time hours, days or years when the external water supply is restricted

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21
Q

what are Pycnogonida

A

sea spiders

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22
Q

what species are Merostomata

A

horse shoe crabs

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23
Q

what species come under Arachnida

A
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24
Q

what comes under Chelicerata

A

merostomata, Arachnidia, Pycnogonida

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25
Q

what comes under Mandibulata

A

crustacea, Myriapoda and hexapoda (insects)

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26
Q

what comes under myriapoda?

A

Diplopoda (millipedes)

Pauropoda

chilopoda (centipedes)

symphyla

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27
Q

what comes under hexapoda?

A

insecta

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28
Q

what do the words arthron and podas mean?

A

•Joint foot/limb

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29
Q

label this diagram

A
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30
Q

label this diagram

A

reptile/bird egg

amniotic

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31
Q

what is classical classification?

A
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32
Q

what is lumpers alternative?

A
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33
Q

what is an endotherm?

A

an animal that can regulate its own body temperature

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34
Q

what is an ectotherm?

A

an animal that cannot regulate its own body temperature

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35
Q

describe feather structure

A
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36
Q

what are the advantages of flying

A
  • Enhances hunting/scavenging
  • Opens up new prey items (flying insects)
  • Facilitates migration, new areas
  • Escape from predators
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37
Q

when did feathered therapods evolve into birds?

A

150 million years ago

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38
Q

what reptilian features have been modified to enable flight?

A
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39
Q

what type of birds are Stuthioniformes

A

•ostrich/rhea/kiwi/emu/cassowary, pectoral muscles not greatly enlarged

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40
Q

what type of birds are Sphenisciformes

A

penguins

flightless but have powerful pectoral muscles used for swimming

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41
Q

what are amniotic eggs?

what are amniotes

A

birds, reptiles, mammals

lay their eggs on land or retain the fertilized egg within the mother

  • Tetrapods that have a terrestrially adapted egg (reptiles/birds, mammals)
  • Shell significantly slows dehydration of egg in air
  • Allows amniotes to occupy wider range of terrestrial habitats than amphibians
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42
Q

what are the four types of bird foot

A

perching: 3 toes forward, one at the back
grasping: 2 forward, two back. vertical tree grasping e.g. woodpeckers
raptor: 3 forward, 1 back, clawed
swimming: webbed

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43
Q

what animal has a single circulatory system?

A

fish

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44
Q

what animals have a double loop circulatory system?

A

mammals, birds, crocodiles, reptiles

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45
Q

mammals vs reptile teeth

A

reptile teeth are uniform

mammal teeth are different

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46
Q

what are mammals?

A

synapsids

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47
Q

what two events cause mammals to radiate

A

Extinction of dinosaurs

  • Fragmentation of continents
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48
Q

what are the changes associated with life on land

A
  • Limb development
  • Bones of pelvic girdle (to which legs attached) fused to backbone
  • No gill slits
  • Ears adapted to detection of airborne sounds
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49
Q

what dos amphibian mean

A

Amphibian means dual lives

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50
Q

what are the characteristics of amphibians

A
  • Most found in damp habitats
  • Rely heavily on moist skin for gas exchange
  • Most have external fertilization
  • Eggs lack shell
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51
Q

what are the three orders of amphibians

A

–Urodela
–Anura
–Apoda

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52
Q

what species are under the order of urodela

A

•Salamanders, superficial resemblance to lizards (limbs, elongated body)
(Newt is salamander that lives in water as an adult

(amphibians)

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53
Q

what species are under the order anura

A

•More specialised than Urodela for terrestrial locomotion
•Powerful hopping hind legs
•Adaptations to reduce risk of predation
–Aposmatic colouration
–Cryptic colouration

frogs and toads (amphibians)

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54
Q

what species are under the order apodans

A
  • Caecilians (worm like, no common name)
  • About 150 species
  • Legless, nearly blind
  • Absence of legs is secondary adaptation
  • Burrow in moist forest soil
  • Do not have dualistic life
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55
Q

what are the other terrestrial adaptattions of amniotes and what period did they arrive in?

A

Relatively impermeable skin (amphibians have moist skin)

Ability to use the rib cage to ventilate the lungs (amphibians pump lungs by ‘gulping’ air)

carboniferous period

Included large herbivores and predators

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56
Q

what comes under amniotes?

A

•Diapsids (reptiles and dinosaurs)
•Synapsids (mammals)
(Anapsids)

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57
Q

describe the skulls of anapsids, synapsids and diapsids

A
  • Anapsid – no openings behind the eyes
  • Synapsid – single opening behind the eyes
  • Diapsid – two temporal openings
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58
Q

what does this skull belong to?

A

anapsid

does not have openings near the temples

belongs to turtles

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59
Q

what does this skull belong to

A

synapsid

belongs to all mammals

60
Q

what is a fenestrae

A

natural (as opposed to traumatic) openings in the skull or other bones in vertebrates

throught to be for muscle attachment in the skull

61
Q

what does this skull belong to

A

diapsid

two temporal openings in the skull

all reptiles:

lizard skull
–Also snakes, tuatara, crocodiles

62
Q

describe the characteristics of reptiles

A
  • Earliest lived approx. 320 mya
  • Have scales that contain keratin
  • Use lungs for gas exchange (cloaca)
  • Fertilization internal
  • Behaviour regulates body temperature
63
Q

describe the characteristics of a crocodile

A

V-shaped snout

Teeth along the jaw line exposed when mouth is closed

Upper and lower jaw about the same width

Olive-brown colouration

64
Q

describe the characteristics of an alligator

A

U-shaped snout

Teeth along the jaw line not exposed when mouth closed

Wider upper jaw, teeth in lower jaw fit into sockets in upper

Blackish colouration

65
Q

what are squamates

A

–Lizards and snakes
Most numerous and diverse reptiles (apart from birds

66
Q

what are these?

A

anal spurs on a snake

he remnants of a pelvis and femur, which have no connection with the spine, simply “float” in the muscle mass.

longer in the males for grapsing during mating

67
Q

what are Testudines

A
  • Perhaps shell derived from dermal plates of parareptiles
  • Tortoises, terrapins, turtles
68
Q

what does this skull belong to?

A

reptilian jaw

69
Q

what does this skull belong to?

A

mammal

70
Q

what is this, what are the labels and what type of animal does it belong to

A

mammal ear drum

71
Q

what is this, what are the labels and what type of animal does it belong to?

A

reptile eardrum

72
Q

what are monotremes?

A

egg laying mammals

  • Lay eggs
  • Have milk but lack nipples
  • Found only in Australia and New Guinea
  • Represented by one species of platypus and 2 echidnas
73
Q

what are marsupials?

A

mammals with pouches

  • Have higher metabolic rate than monotremes
  • Have nipples
  • Give birth to live young
  • Have placenta
  • Born early in development, complete embryonic development in marsupium
74
Q

what are placental mammals?

A

mammals with placentas

  • Have more complex placenta than marsupials
  • Have longer period of pregnancy
  • Living orders originated in late Cretaceous
75
Q

label this skeleton

A
76
Q

what is an extanct species?

A

a species that isnt extinct and still exists

77
Q

how many extant taxa can fly

A

1 in 3 can fly and 1 in 2 are functionally terrestrial

78
Q

what other taxa can fly?

A

birds, bats (mammals),

79
Q

what does this tagmosis belong to?

A

annelid (worm)

80
Q

what does this tagmosis belong to?

A

myriapod

81
Q

what does this tagmosis belong to?

A

chelicerate (arthropods)

82
Q

what does this tagmosis belong to?

A

hexapoda (insects)

83
Q

what tagmosis does this belong to?

A

crustacea

84
Q

what are the features of pycnogonadia?

A

sea spiders
•4,5 or 6 pairs of walking legs
•Live on sessile animals
•Highly derived mouthparts form proboscis
•Male carries eggs

85
Q

what are the characteristics of merostomata?

A
  • Aquatic
  • Spike-like telson
  • 5-6 pairs of abdominal gills
  • Subclasses: Xiphosura and Eurypterida
  • Eurypterida now extinct.
  • Apex predators 450mya
  • Up to 2m long
86
Q

what are the characteristics of xiphosura?

A

horse shoe crabs

  • Soft-bottom, shallow water marine chelicerates
  • Prosoma covered by large carapace
  • Abdominal segments fused together
  • Omnivores and the only chelicerates that can eat solid food
87
Q

what are setae for?

A

-Chemoreception
-Mechanoreception
-Propioreception
-

88
Q

what are trichobothria for?

A
  • Heavily innervated
  • Elongate setae
  • Detect air currents-
89
Q

what are the terrestrial adaptations of arachnidia?

A

Waxy epicuticle, Book gills modified to book lungs & tracheae, Appendages adapted, Silk in spiders, pseudoscorpions, mites

90
Q

what is the difference between venom and poison?

A

venom is directly applied and poison isnt (so the insect might be poisonous when eaten but doesnt inject poison into another animals skin)

91
Q

what are pectines?

A

sense organs,

92
Q

define viviparous

A

live bearing (young)

93
Q

Venom glands opening near tips of chelicerae is unique to the

A

arachnae

94
Q

what are the only arachnids to produce silk?

A

spiders

Spiders are the only arachnids with appendages for silk production

Silk is produced in abdominal glands and released via spigots

Used in prey capture and/or immobilization

95
Q

what are ambypygids?

A

Sometimes called ‘Whip Spiders’

100 known species

Carnivorous, generally nocturnal

Distinctive pedipalps

Specially modified 1st pair of legs modified to be sensory organs

96
Q

what are acari?

A

Unique lack of tagma: Gnathosoma (anterior), Idiosoma (posterior)

important economically, eat mostly leaf litter - detritovore

Unique body plan shows almost complete fusion of Cephalothorax and Abdomen to form Idiosoma. Gnathosoma is a feeding structure.

97
Q

which chelierate can eat solid food

A

•Cannot eat solid food, external digestion, Except mites with varied modifications

98
Q

what does CAM stand for?

A
  • crassulacean acid metabolism

lAt night
–Stomata open at night
–Atmospheric CO2 taken up by phosphoenolpyruvate (PEP)
–converted to malate; stored
lDuring day
–broken down to pyruvate & CO2
CO2 passes into normal C3 photosynthesis

99
Q

gas relations in hot environments?

A

Hot environments

lCO2 can be limiting
–decreased CO2 solubility
–control water availability
l
CAM photosynthesis
C4 photosynthesis

100
Q

what is a biome?

A

biome refers to the life forms of a specific terrain/climate area.

rainforests, tundra, grassland, savanna etc

101
Q

what are some tundra plant adaptations?

A

lSmall leaves
lThick cuticles
lDense hairs
lPlants protected by lichens
lDesiccation tolerant
lBiomass within soil
lFlower buds dormant
lFlower structure traps heat
l

102
Q

what are some unique features of flowers?

A

–Reproductive – Flowers
•Bisexual
•Enclosed female parts
•Dominant flower structures

103
Q

how many parts do flowers usually have?

A

4

sepals:

petals

stamens

carpals

104
Q

who was george cuvier

A

Cuvier understood that extinctions had been common event historically, did not believe in evolution of new species.

105
Q

Local extinctions often lead to

A

global extinctions

106
Q

is evolution the exception or the rule and why

A

•Populations survive without change if possible.

If the environment changes:-

Few species evolve. Most become extinct.

Evolution is the exception rather than the rule

107
Q

who was Stephen Jay Gould

A

he estimated that 99% of all species that ever lived are now extinct. •Ability to evolve depends on hereditary variation in the gene pool. •Most species are not sources of great future diversity.

108
Q

when did the lungfish evolve?

A

400mya

Were once an active and diverse group.

One branch evolved onto land.

Remaining lungfish evolution slowed down.

Land vertebrate evolution exploded

Now just a few lungfish remain.

109
Q

extinction occurs when

A

•More individuals die (or in the case of local extinction, emigrate) than can be replaced by reproduction (or immigration).
•
•Small populations can die out due to chance fluctuations, eg a few bad seasons.

110
Q

Small population size and limited geographical range =

A

vulnerable to extinction

111
Q

what could global warming cause in reptiles?

A

•cause sex imbalance in reptiles where temperature of egg incubation influences gender.

112
Q

when did the earth form?

A

hadean 4.5-3.9 billion years ago

113
Q

what happened in the archean period?

A

3.9-2.5 billion years ago

Earth’s crust formed, volcanic activity

Prokaryotes, including cyanobacteria and oxygen

114
Q

what happened in the Proterozoic era

A

2.5 billion– 540 mya billion years

eukayrotes

mountains formed, oxygen levels rise

115
Q

what are rangiomorphs

A

Deep sea

One of first ever complex organisms

Fractal construction

Animal

Unable to move

116
Q

what happened in the cambrian era

A

Sponges, corals, echinoderms, trilobites dominant. Marine algae, no land plants. (End Cambrian Mass Extinction)

540-490 mya

117
Q

what happened in the ordovician era

A

Early vertebrates armour plated fish. Late Ordovician Mass Extinction.

490 - 443 mya

118
Q

what happened in thr Silurian era

A

443 - 417mya

Sea life dominated by corals, arthropods, crinoids, nautilus, fish jaws evolve, first sharks. Psilotum early land plant

119
Q

what happened in the devonian period

A

Armoured fish, lungfish, sharks, ammonites, spiders mites.

Mass Extinction 370 mya

417-354mya

120
Q

what happened during the carboniferous period

A

Armoured fish extinct, marine crinoids, brachiopods. Insects-cockroaches, reptiles, cycads, ferns, coal deposits

121
Q

what happened during the

Permian

290-248 mya

A

Rich invertebrate marine life at start, then Mass Extinction 245 mya

122
Q

what are stamens also known as

A

microsporophylls

filiament and anther (pollen)

123
Q

what are carpels also known as

A

macrosporophyls

stigma, style, ovary

124
Q

what is this?

A

male anther structure sac with pollen filament

125
Q

what is this?

A

pollen grain

produced by meiosis of microspore mother cells that are located along the inner edge of the anther sacs

126
Q

label this correctly

A
127
Q

label this correctly

what are the two cells within this pollen grain

A

tube cell (left)

generative cell (right)

128
Q

what is this and what are the correct labels

A
  1. ovary wall
  2. integuments
  3. megasporangium wall
  4. embryo sac

part of a plant ovary

129
Q

what is the life cycle of an angiosperm

A
  • Anther pollen
  • Pollen to stigma (Pollination)
  • Germinates
  • Tube style into ovule
  • Tube sperm into embryo sac
  • Sperm & egg, zygote (Fertilization)
  • Ovule seed
130
Q

describe angio sperm double fertilisation

A

•Fertilization - Double Fertilization–One sperm cell (N) fuses with egg (N) > zygote (2N)
–One sperm cell joins two polar nuclei > endosperm cell (3N)
•endosperm cell (3N): plant equivalence of yolk
contents exported to cotyledons (zygote) which serve as nutrient supply in developing embryo before photosynthesis starts.

131
Q

describe double fertilisation

A

•Fertilization - Double Fertilization–One sperm cell (N) fuses with egg (N) > zygote (2N)
–One sperm cell joins two polar nuclei > endosperm cell (3N)
•endosperm cell (3N): plant equivalence of yolk
contents exported to cotyledons (zygote) which serve as nutrient supply in developing embryo before photosynthesis starts.

132
Q

how do plants avoid imbreeding?

A
  • Imperfect Flowers
  • Dioecy. The imperfect flowers present on separate plants. Dioecy is the equivalent of the separate sexes of most animals. Example: Holly
  • Monoecy. The imperfect flowers present on the same plant, but mature at different times. Example: Maize

•Perfect Flowers
•Heteromorphic flowers. The flowers are perfect but two structural types; for example
–long stamens with a short style and
–short stamens with a long style.
a single plant has one type

133
Q
A
134
Q

what are heteromorphic flowers

A

If the pollinator has a short tongue, pollination is favored from thrum to pin - but not the reverse.

135
Q

what is a homomorphic flower

A

•All flowers have exactly the same structure. Avoidance of self-fertilization depends on genetic/biochemical mechanisms.

136
Q

what is
•Sporophytic self-incompatibility (SSI)

A

phenotype of the pollen is determined by the diploid genotype of the anther

Pollen will not germinate on the stigma of a flower that contains either of the two alleles in the parent that produced the pollen.

e.g. Brassica

137
Q

what is
•Gametophytic self-incompatibility (GSI)

A

most common type

phenotype of the pollen is determined by its own gametophytic haploid genotype

Incompatibility is controlled by the single S allele in the haploid pollen grain.

A pollen grain will grow in any pistil that does not contain the same allele

e. g. S2 pollen from an S1S2 parent will grow down an S1S3 style.
e. g. Solanaceae

138
Q

what are the sucesses of angiosperms

A

•Many features favour out-breeding
–More variability, better fitness
•Many features favour efficiency
–More resources other activities
•Style encourages competition
–Better fitness

139
Q

If 40 million are alive today how many will go extinct each year?

A

10

Average lifespan of a species in fossil record = 4 million years.

One species in 40 million dies a ‘natural’ death each year.

140
Q

how many mass extinctions were there?

A

5 (or 6)

141
Q

mass extinctions…

Are survivors fitter or luckier

A

Sudden environmental catastrophe gives no chance for evolution.

Species can run out of niche.

Eg Island sinks, or host species dies – Dodo flea

142
Q

what mass extinction killed the dinosaurs?

A

K-T killed approx 66% of living species, including dinosaurs.

Meteorite = 10 Km diameter. Blast = 10 million Mega tonnes TNT All worlds nuclear weapons x 10,000.

143
Q

list the steps the KT extinction had on earth

A
  • Before impact:- Shockwaves as meteorite travelled through air.
  • On reaching earth:- went through 1 Km deep ocean – earths crust.
  • Minutes after impact:- Earthquakes,

100 foot tidal waves – coastal areas.

But all the above are mainly local affects.

  • Site of impact had large amount of sulphur which was released.
  • Minutes after impact :- billions of tonnes of debris blasted into space, 3-4 x mass of meteorite, at speeds great enough to leave earth’s gravity.
  • 30 – 60 minutes after impact:- sky would glow red hot with debris re-entering earth’s atmosphere, - global fires.

•1 hour – 6 months after impact :- sky would cool and blacken to darkness.

Sulphur ejected – sulphuric acid, acid rain, block sunlight, - global cooling.

•6 months – 10 yrs after impact:- cold winter conditions, little sunlight.

144
Q

populations likely to die out today are:

A
  • Small populations with a limited range.
  • Short lived species.
  • Slow rate of reproduction.
  • Those with fluctuating numbers.
  • Those which occupy a fluctuating environment.
145
Q

what happened to the cheetah

A
146
Q

what happened to the northern sea elephant

A
  • Population bottleneck in 1890s, down to 20 individuals due to hunting by humans.
  • Now little genetic
  • variability
147
Q

in what ways do humans cause extinction

A
148
Q
A

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