exam Flashcards
4 basic animal tissue types + important feature
- Epitheleal: cover body surface and line organs
- muscular: locomotion
- connective: support
- nervous: electrical impulses
Types of anatomical symmetry
- Radial (biradial, pentaradial)
- Bilateral
- assymetrical
Developmental diff between protosomes and deuterostomes
Protostome (first mouth)
- schizocoelous coelom
- trochophore larva
- blastopore forms mouth
- anus developed last
Deuterostomes (second mouth)
- enterocoelous coelom
- blastopore forms anus
- mouth developed last
schizocoelous development
- mesoderm forms at base of pore
- mesoderm splits, forms cavities
- blastopore forms mouth
- anus forms at other end
enterocoelous development
- mesoderm forms at top of pore
- archenteron outpockets
- coeloms formed
- anus forms from pore
types of tissue layers
- unicellular
- diploblastic
- triploblastic
layers of diploblastic
- ectoderm
- endoderm
layers of triploblastic
- extoderm
- endoderm
- mesoderm
patterns of coeloms
- acoelomate (none)
- pserudocoelomate (ring)
- coelomate (2 halves)
4 super groups of animal like protsists
- Excavata (excavated feeding groove, anaerobic)
- amoebozoa (have arms for moving, phagocytosis for feeding)
- rhizaria (characteristic of amoeba)
- alveolata (variable)
metazoans are ___ flagellated cells
mono
evolutionary implications of multicellularity
bigger = predation risk, mobility, reproduction
proferians
Pore bearer — corals
- no tissues or organs
- asexual and sexual
- male and female function
Cnidaria (stinging)
- diploblastic
- gaterovascular cavity
- nerve net
- cnidocytes (stinging cells)
- Alternation of gens
- hydrostatic skeleton
alternation of gens - cnidaria
- polyp
- budding
- medusa
- egg
- fertilized
- zygote
- blastula
- planula
- polyp
ctenophora (comb bearer)
- diploblastic
- complete digestive system
- nerve net
- monoecious
- external fertilization
why might choanoflaggelates be sister group of metazoans
- collar cells in metazoans, choanocutes in sponges
- choanoflaggelates - homologous cell signalling (not in other euks)
- DNA supports clade
Identify features that unite Lophotrochozoans.
Trochophore larva or lophophore larva
Describe how the nervous and excretory systems are more complex in turbellarians compared to those of cnidarians?
Protonephridia (kidney)
- flame cell at end of each tubule
- beats + pushes water through
- nurtients absorbed, waste exreted
Nervous system
- cerebral ganglia
- sensory and motor nerves
Understand general anatomical features of turbellarians (flat worms - free living)
- no body cavity
- cephalization
- no circulatory system
- asexual and sexual
Describe the general life history of digenean trematodes.
- adult in sheep or human
- coppulate
- eggs released into digestive tract
- excreted in feces
- intermediate in water
- eaten by snail
- becomes sporocyte
- asexually reproduces — makes many new sporocytes
- some leave and find new snail to repeat
- some produce rhei
- produce embryonic cells
- turn into cecaria (second larval form)
- released in water
- find plant
- becomes metacercaria
- eaten by human or sheep
Understand general anatomical features of tapeworms.
- scolex = “mouth”. attach
- strobillus = repeating proglottids
- each has reproductive system
life cycle of cattle worm
- in human
- coppulate in mature proglottid
- structure breaks down
- gravid proglottid now has sacs of eggs
- excreted into host — feces
- eaten by cattle
- eggs imbed into tissue and form cyst as they hatch
- humans eat uncooked meat with eggs
Describe the general molluscan body form.
- triploblastic
- coelomate
- head-foot and viseral mass
- mantle and mantle cavity
- radula
- trochophore larvae
- open circulatory
- shell
why do gastropods do torsion
- rotate 180 degrees
- put mantle cavity over head
- protection
how are organs affected by shell coiling in snails
- pairs —> single
- highly vascularized mantle
functino of mantle in gastropods
gas exchange
waste removal
function of mantle in bivalves (muscles, clams)
Make shell
pump water for feeding
continuous contact with water
functino of mantle in cephlapods (squids etc)
(cephla - head, pod - food)
propulsion
Describe how the anatomical characteristics unique to molluscs have
been modified in cephalopods
Molluscs : head foot
Cephlapods: arms/tentacles, siphon
Indicate the features of cephalopods that make them effective
predators.
- large brain
- well developed eyes
- jet propulsion
Describe some attributes of cephalopods that are indicative of a very
complex nervous system.
- large brain
- eye sight
- learning and memory
- observational learning
Differentiate between the phenomena of metamerism and
tagmatization.
Metamerism
- segments of body
Tagmatization
- specialization of the body regions
• Compare general anatomy of the Errantia and Sedentaria clades.
Errantia (erran, free moving — worms, scary looking , like millapeded)
- parapodia with prominent lobes
- well developed pals
Senendatria (seddentary, unmoving)
- parapodia with reduced lobes
- stiff body wall
- reduced palps
Compare reproductive characteristics of Errantia and Sedentaria.
Errantia (free moving, aquatic worms)
- mostly dioecious
- gametes released as trochophore larva
Sedentaria
- monoecious
- eggs laid in cocoon
Describe structure and function of metanephridia.
- fluids move through open cilliated funnel
- nutrients absorbed
- waste ecreted
dentify features common to Ecdysozoans.
(ecto - to shed, molt)
- cuticle
- priodically molt
Describe the structure of the cuticle in
nematodes and why it is important.
- collagenous
- maintain internal hydrostatic pressure
- protection
Describe the filarial worm life cycle.
MOSQUITO WORMS
- coppulate and release eggs in lymphatic vesicles in host
- into blood strem
- mosquito feeds, eats eggs
- eggs molt twice
- mosquito eats again
- injects larvae into new host
- molt twice
- enter lymphatic vesicles
Outline four key features that led to evolutionary success of arthropods.
Exoskeleton
Metamerism/tagmentization
Hemocoel
Metamorphisis
Compare embryonic development of
hemocoel v.s. coelom.
Hemocoel
- mesoderm forms on pore
- coelum forms
- mesoderm grows around it and other structures
- coelum does not grow
- cavity = hemocoel
Coelom
- expands with mesoderm
major arthropod lineages
Triplomorpha (extinct, triplo - 2, morpha - body, 3 body segments)
- head, thorax, pygidium
Chelicerata (chele = claw/pinchers)
- first land animals
- 2 tagmata
Myriopoda (10 000 feet, millipedes, centipeded)
- 2 tagmata (head, trunk)
- one or two pairs of appendages per body segment
Crustaceans
- paraphyletic
- biramous appendages (2 branches, like claws)
hexapoda (6 feet) — flies
- 3 tagmata
- 5 pairs appendages, includes wings
malacostraca — crustaceans
malakos = soft, soft shell
shrimp, lobster, crab
copepoda — crustaceans
cope = oar, podos = foot
branchiopoda — crustaceans
gill foot
leafy appendages
brine shrimp. fairy shrimp, water fleas
respiratory insects
branching trachea and tracheoles
gas exchange
one spiracle per segment (leads to outside)
excretory insects
- tubules from gut to hemocoel
- ions actively transported
- water passively flows
- uric acid secreted
- reabsorbtion
- excretion
What features differentiate echinoderms from animals previously
discussed?
Echinoderms (echino - spiny, derm - skin)
- star fish, urchins etc
- deuterostomes (second mouth)
- radial symmetry
- water vascualr system
- nervous system
What anatomical features are unique to echinoderms?
- water vascular system for movement
- central ring
- tube feet with bulbs at top
- suction cup at bottom
Describe the water vascular system and its functions.
- tube feet = water filled canals
- ring canal surrounds mouth
locomotion
feeding
gas echange
sensory
Describe skeletal elements present in echinoderms.
- ossicles extending from mesoderm
- covered by epidermal layer
- if skin broken, ossicles becomes spine
Describe the general body structure of hemichordates.
Hemichordates (hemi = half, half chordate)
- chordata (chord — have notochord)
- have stomochord
- weird worm things
- deuterostome
- 3 tagmata
Proboscis (sucking organ)
Collar (around mouth)
Trunk (main body) - tripartite coelom
- open circulatory
- cilliated pharyngeal slits
- dorsal nerve chord (stomachord)
What anatomical feature is shared by echinoderms and
hemichordates?
3 part coelom
How does the nervous system of hemichordates differ from the
nervous system of annelids and arthropods?
Hemichordates
- nerve chord
- no major ganglia
Annelids — ring like, WORMS
- nerve chord
- ganglia
Arthopods - jointed leg, spiders, insects, crustaceans etc.
- ganglia
- dorsal brain
Name four anatomical features that are unique to chordates.
- notochord
- pharyngeal slits
- dorsal tubular nervous system
- paired trunk muscles
- thyroid gland
Why is the evolution of jaws and paired fins considered to be a major
evolutionary development?
diversification of chordates
Describe counter-current exchange and understand why it is
important.
- Water flows over gills
- Blood flows in opposite direction
- constant oxygen exchange
Water has 2.5% the oxygen the air has — need more “breathing”
Describe features of fishes that are adaptive to aquatic environments
- swim bladder
- fins
- bony scales - protection, camouflage, regulation
- lateral line system - sensory
Contrast challenges associated with living in aquatic versus
terrestrial habitats.
Aquatic
- supported by dense water
- low oxygen
Terrestrial
- use energy to counter gravity
- high oxygen
Identify anatomical and physiological features that differ in
aquatic and terrestrial animals.
- lighter skull
- neck mobility
- stronger skeleton
- improved muscles / reorganized limbs
- better respiration
Contrast circulatory systems of bony fishes versus amphibians.
Bony fish
- 1 atrium and 1 ventricle
- gills for gas exchange
Amphibeans
- 1 atrium and 1 ventricle
- lungs for gas exchange
- partially splot atria (seperate oxygenated and deoxygenated blood)
- circulate to skin
Identify adaptations that allowed reptiles to further abandon aquatic
environments in favour of terrestrial environments.
- amniotic egg
- water resistant skin
- claws
- neck mobility
- repiratory
- kiney
- limb articulation
Describe the amniotic egg and explain its significance.
Egg of reptiles, birds, mammals
- has additional embryonic membrane
- allows for eggs to be hatched on land
ndicate why the traditional taxonomic arrangement of vertebrate classes
(i.e. reptiles, birds, and mammals) is problematic.
- morphological variability
- evolutionary relationships
- inclusion of amphibians
Identify the distinguishing features of birds.
- only current amniote with feathers
- skeletal for flight
- bill (no teeth)
- hard shelled eggs
Identify the distinguishing features of birds.
- single occiptal condyle
- single middle ear ossicle
- air spaces in bone
- nucleated red blood cells
- feathers
- nesting
Describe anatomical features of birds that are associated with flight.
- hollow bones
- flight muscles
- feathers
- wings
Describe anatomy of mammalian skin and associated structures.
Epidermis
- open of pore
Dermis
- glands
- vascular
- hair
- nerves
Fat
- vascular
- hair base
mamalian vs reptilian skeleton
Mammalian
- 5 vertebral regions
- have cervical region
- single bone in lower jaw
- appendages below body
- multiple ossicles
Reptilian
- lack cervical region
- multiple lower jaw bones
- appendages outward from body
- one ossicle
