Exam 3 Flashcards
animals
- multicellular, ingestive heterotrophs
- unique tissues for impulse control and movement: nerves&muscles
- except sponges
life history
pattern of development & growth from inception to maturity
animal life history
- sexual reproduction
- diploid
gastrulation
The process in which the embryo develops into a gastrula following blastulation
gastrula
an embryo at the stage following the blastula, when it is a hollow cup-shaped structure
blastula
embryo that is a hollow ball of cells
archenteron
- cavity of an embryo at the gastrula stage.
- develps into the gut
blastopore
opening of the central cavity of the gastrula
germ layers
- ectoderm-originates from outer layer of germ cells
- endoderm-innermost layer
direct development
development without a metamorphosis
indirect development
metamorphosis
hox genes
- specific 180 nucleotide-long sequence
- cnidarians->humans
- determine
- cell identity
- developmental pathways of cells
hox genes tell cells ________
where and when to divide
animals are ________
- monophyletic
- Protometazoan resembled choanoflagellate protist
Body plan
- body oranization
- embryonic germ layers
- symmetry and cephalization
- segmentation
- appendage# and form
___________ have helped us understand animal history
fossil deposits
Why did diversification happen so fast
- ecological reasons
- predator-prey relationship
- geologic
- increasing o2 levels
- genetic causes-hox gene
- duplication and divergence
phylum porifera
- common name: sponges
- no tissues
- assymetry
- one to many structural cavity, no true body cavity
porifera organ systesm
support from gelatinous mesoglea
porifera special cells
- choanocytes–food capture
porifera feeding
- fliter feeding
- no digestive organs
- intracellular digestion only
porifera reproduction
- sexual
- hermaphrodites
- sperm dispersed into water
- external fertilization
- zygotes develop into mobile larva
- planktonic larval stage
- asexual
- fission
- fragmentation
porifera ecological niches
- primary consumer
- planktivore
- rarely eaten
porifera habitat
aquatic (mostly marine)
phylum cnidaria
common name: jellies, corals, anemones, hydroids
cnidaria tissues?
- yes, diploblastic
- ectoderm and endoderm
- mesoglea between
cnidaria symmetry
radial
cnidaria cavities
one–gastrovascular
cnidaria organ systems
mouth and tentacles
cnidaria special cells
- cnidocyte
- stinging cells of jellyfish
cnidaria feeding
- suspension feeding
- mass feeding
- photoautotropic symbionts
cnidaria reproduction
- budding, fission, fragmentation
- sexual w/ external fertalization
cnidaria habitat/echological niches
- freshwater, marine
- planktonic (drifting)
- or benthic (bottom-living)
- corals may be solitary or reef-building
coral bleaching
- coral ejects algae that causes color
- CO2 in atmosphere is absorbed in ocean and makes water more acidic by creating carbonic acid
- changes in ocean chemistry can disrupt entire food web
why study protosomes?
- major ecologic consumers
- medical models
- economic impact
- diversity
bilatarian synapomorphies
- bilateral symmetry
- cephalization
- triploblasty (+mesoderm)
- coelom variously developed
coelom
- fluid-filled body cavity
- contributes to ‘tube w/in a tube’ body plan
- lined by mesoderm
- distinct from gut
coelomate
acoelomate
pseudocoelomate
pseudocoelom surrounded by muscle layer
coelom function
- cushion (protection)
- spaces for organs
- isolate simultaneous body functions
-
hydrostatic skeleton
- fluid filled cavity against which muscles can contract
Bilaterians are divided into two lineages based on
- blastopore fate
- coelom development
Lophotrochozoa characteristics
- clade w/in protostomes
- protosomes
- synapomorphy-genetic sequences —hox genes and rRNA
lophophore
a horseshoe-shaped structure bearing ciliated tentacles around the mouth in some lophotrochozoa
phylum platyhelminthes
flatworms, master parasites
platyhelminthes synapomorphy
genetic sequences
platyhelminthes habitat
aquatic and animal bodies
platyhelminthes cavity
gastrovascular/no cavity
platyhelminthes coelom?
acoelomate
Platyhelminthes reproduction
- sexual
- internal fertilization
- oviparous
- asexual
- parthenogenic
parasite adaptation
- small size & more surface area
- absorption of nutrients across body wall
- very high fertility
- complex lifecycles w/ intermediate host
phylum rotifera
- “wheel animals”
- tiny aquatic predators
rotifera Synapomorphies
- trophi
- aquatic–marine/fresh
- v tiny
- pseudocoelom
- complete digestive tract
- sexual and asexual (parthenogenic)
parthenogenic
embryo develops fron unfertilized egg
trophi
muscular throat w/ jaws
‘toes’ w/ adhesive glands
why study rotifera
- scientific model for longevity (cryptobiosis)
- some species have no males
- primary consumers
cryptobiosis
a physiological state in which metabolic activity is reduced to an undetectable level without disappearing altogether
phylum Annelida
- segmented worms are ecosystem engineers
- earthworms, bristle/fan worms, leeches
Annelida synapomorphy
- >=1 pair chitinous setae (chitae)
- mostly marine, some freshwater/damp soil
- coelom
- segmented and metameric
- complete digestive tract
- sexual(hermaphrodites) and asexual
- Trochophore larvae
Trochophore larvae
the planktonic larva having a roughly spherical body, a band of cilia, and a spinning motion
metameric
having a linear series of body segments fundamentally similar in structure, though not all such structures are entirely alike in any single life form b/c all carry out diff functions
Phylum Mollusca
- greatest diversity in body plan variants
mollusca synampomorphies
- shell-secreting mantle
- scraping radula
- muscular, clinging foot
- mostly marine, few fresh/terrestrial
- coeomate
- trochophore larvae
- sexual reproduction
- hermaphrodites
- separate sexes
hermaphrodite
animal having both male and female sex organs
Class Cephalopoda
- chromatophores: cells that enable rapid color changes used for camoflage and communication
- phylum mollusca
Phylum Nematoda
- roundworms
- pseudocoelom
- support: hydrostatic skeleton
- thin, translucent cuticle
- impervious to digestive enzymes
- can only lengthen/shorten body. no muscles to thicken or thin
nematoda limbs/segmentation
- no limbs
- no segmentation
nematoda habitat/ecology
- terrestrial,marine,freshwater
- few endoparasitic on humans&pets
- little understood, but by mass most multicellular life onplanet is Nematoda
- decomposers
endoparasitic
a parasite that lives in the internal organs or tissues of its host
Nematoda feeding
- complete gut-mouth and anus
- Some have a piercing mouthpart-made from hardened cuticle
- few parasicic but important
- plant parasites
- filiarial diseases from guinea worms
- lymphatic/ocular
Phylum Arthropoda
- Body Cavity: reduced coelom
- Support: chitinous exoskeleton
- limbs with joints
- Head/trunk segments (trunk can be abdomen&tail)
arthropod habitat/ecology
- marine, freshwater, terrestrial
- primary, secondary consumers, parasites
- may live in social systems
- vectors of disease and pollen
protostome
pore becomes mouth
deuterostome
pore becomes anus
arthropod feeding strategy
jointed limbs grown as mouth parts for feeding, courtship, defense, movement, or sensory perception
Arthropod life cycle/reproduction
- sexual
- dioecy
- internal fertalization
- courtship displays, sperm storage, nuptial gift
- indirect development
- 1 to many larval stages
- ecdysis
dioecy
has distinct male and female individual organisms
molting
ecdysis
hemimetabolous
- infomplete, nymphs loook like mini adults
- same habitat/food source
holometabolous
- complete, discinct larval stage
- different body, food, habitat
feeding efficiency
reduce competition among life stages
arthropod functional specialization
- larva specialized for feeding, sessile
- adult specialized for reproduction, mobile
- leads to higher efficiency in feeding and reproduction—>higher fitness
exoskeleton advantages
- use of terrestrial environment
- stiff site for muscle attachment
- keep animal from drying out
- protection against chem and mechanical trauma
Disadvantages
- requires resources to make
- limits growth
- animal is vulnerable during ecdysis
subphylum chelicerata
- aracnids, horshoe crab, sea scorpions
- no antennae
- cephalothorax and abdomen
- 6pairs of appendages including chelicerae
subphylum myriapoda
centipedes, millipedes
subphylum crustacea
- fairy shrimp, krill, lobster, crab
- 2 pair of antennae
- jaw-like mouthparts
- head may fuse w/ segments to form carapace
class insecta
- beetles, flies, etc
- 1 pair of antennae
- compound eye
- head
- thorax
- 2prs wings 3 prs legs
- abdomen
phylum echinodermata
- bentameric symmetry
- bony plates form an endoskeleton
- water vascular system
- mutable connective tissue
water vascular system form
- canals and tube feet
- function
- locomotion
- nutrient exchange
- gas exchange
mutable connective tissue
- enables movement
- dramatic effect in defense
phylum chordata
- master hunter
- synapomorphies
- notochord–flexibal, dorsal endoskeletal rod between nerve cord and gut
- dorsal, hollow nerve cord
- pharyngeal slits
- lateral openings in foregut body wall
- supported by stiff arches
- gas exchange and feeding efficiency
- post anal tail containing muscular/skeletal elements–POWER
jawless fish
- hagfish/lamprey
- eel-like body
- no paired fins
- mouth fleshy w/ no bones
- fibrous/cartilaginous skeleton w/ persistent notocord
- move by undulation
hagfish
- no jaws
- no paired appendages
- poor eyes
- Marine only
- Free-living (not parasites)
- Scaevnging
- mucus covered
lamprey
- no jaws/paired appendages
- well-developed fins
- Ectoparasitic
- suck blood using oral disk
- Reproductive migrations “anadromy”
- juveniles live in saltwater
- adalts breed in freshwater
Jaws allow
- dismember larger food items/prey
- facilitated development of teeth
- active predator defense
- de-emphasize armor as passive defense
- more mobility
- all these=many many vertebrates
chondrichthyes
- cartilagenous fishes
- sharks, rays, etc
- cartilaginous endoskeleton
- 5-7 separate gill slits
- electro/chemosensory ablilties
Chondrichthyan Reproduction
- oviparity
- ovoviviparity
- viviparity
oviparity
- egg laying
- bullhead sharks, rays
ovoviviparity
- retain eggs in uterus
- yolk sac attached directly to digestive system
- additional nourishment may be derived from other eggs
- sand tigers, whites, threshers
viviparity
- most complex
- when yolk gone, empty sac attaches to uterine wall
Class Actinopterygii
- most species rich vertebrate
- endoskeleton of bond/cartilage
- fishes w/ thin fin rays
- may have swim bladder
lobe fined fishes
- paired fins have their own blood vessels, may have bony elements
- homologous to legs
Lungfishes
- Freshwater
- Hard bones support thin fleshy side fins
- swim bladder connected to esophagus, can exchange CO2 for O2
- seek new homes during droughts
Tiktaalik
- fish-tetrapod intermediate
- no opercula
- air breather
- scales&ribs
- neck
- fin bones
Amphibians
- first tetrapods
- mostly terrestrial and freshwater
- Many–> indirect development
Class Amphibia
- frogs and toads, salamanders etc
- chytrid fungi + Climate change=severe metomorphosis problems
- climate-driven vegetation change
Amniotic egg
- birds, reptiles, some mammals
- extraembryonic membranes
amniotes have __________ fertilziation
internal
amniotes-prevent dessication
- waterproof skin made of keratin
amniotes internalized gas exchange
lungs and rib cage for efficient gas exchange
mammal synapomorphy
- hair
- made of keratin
- endothermic
- maintains constant body temp
- also in birds
- lot of parental care
- mammary glands
monotremes/marsupials
- young very helpless
- no placenta
- fossils found isolated
monotremes
- lay eggs
- platapus-venemous
- echidna–eggs hatch in pouch
marsupials
give live birth, young develop in pouch
placental mammals
- viviparity only
- placenta–nourish developing embryo (parental care)
- most species rodents
- some have flight/sea
reptilia:lizards/snakes
- thermosensory
- can run, undulate or glide
snake adaptations
- ancient types have pelvis
- loss of left lung
- jaw flexibility
reptilia:tortoises/turtles
- terrestrial, freshwater, few marine
- vertebra/ribs fused to tough keratin shell
Reptilia: Crocodiles & Alligators
- freshwater/marine
- carnivory/scavenging
- aquatic adaptations
- endangered
crocs/alligator:mix of old and new
- oviparous (old)
- Parental Care (new)
- poikilothermic (old)
- 4-chambered heart (new)
poikilothermic
internal temperature varies considerably
reptilia: aves
- birds
- closest living relative to dinos
- shelled eggs, scales on legs
- parental care
-
endothermic
- maintain constant internal body temp
aves adaptations for flight
- weight reduction
- fewer organs
- hollow air sacs in bones
- huge flight muscles
-
feathers
- made of keratin
- structure resists flow of air
- airfoil
cephalization
the concentration of sense organs, nervous control, etc., at the anterior end of the body, forming a head and brain
radula
anatomical structure that is used by mollusks for feeding,
gastrovascular cavity
digestion and circulation in Cnidaria and Platyhelminthes (flatworms)
setae
a stiff hairlike or bristlelike structure, especially in an invertebrate.
notochord
a cartilaginous skeletal rod supporting the body in all embryonic and some adult chordate animals
tube feet
each of a large number of small, flexible, hollow appendages protruding through the ambulacra, used either for locomotion or for collecting food and operated by hydraulic pressure within the water-vascular system.
hydrostatic skeleton
The system of support found in soft-bodied invertebrates, which relies on the incompressibility of fluids contained within the body cavity
