Chapter 27 - Animals Flashcards
How many living species of animals have been identified?
1.3 million
“The animal kingdom extends far beyond
humans and other animals we may encounter”
True or False?
True
Are animals heterotrophic or autotrophic?
Heterotrophic
How do animals consume nutrients?(Not specific nutrition mode)
They ingest their food
Are animals multicellular or unicellular?
Multicellular
What domain do animals belong to?
Eukarya
What do animals cells lack that plant cells have? (1)
They lack cell walls
How are animal bodies held together?
By structural proteins
What is one kind of structural protein?
Collagen
What two tissues are unique to animals?
Nervous tissue and muscle tissues
How do most animals reproduce?
Sexually
What stage dominates the animal life cycle?
The diploid stage
What percentage of the animal kingdom is extinct? (Species)
99% of species
What is greater in the animal kingdom, the diversity if living species or the diversity of extinct ones?
The diversity of extinct species
In what time range did the common ancestor of living animals and choanoflagellates live?
Between 675 to 875 million years ago
How do zoologists categorize animals?
They categorize them by body plan
What is a body plan?
A set of morphological and developmental traits
What is one defining category of an animal’s body plan?
Symmetry or a lack of symmetry
What kind of symmetry can animals have
Radial or bilateral
What 3 sets of positions occur with bilateral symmetry?
Dorsal and ventral
Right and left
Anterior and posterior
The organization of the animal’s …… can change the animal’s body plan.
Tissues
What are tissues?
A collection of specialized cells
How are tissue cells isolated?
They are isolated from other tissues by membrane layers
What layers are present during deveopment in animals and how many layers are there?
Germ layers
Three
What do the three germ layers give rise to? (2)
The tissues and organs of the animal embryo
Define: Ectoderm
The germ layer covering the embryo’s surface
Define: Endoderm
The archenteron
Define: Archenteron
The innermost germ layer lining the developing digestive tube
Define: Diploblastic
Animals with both an ectoderm and endoderm
Define: Triploblastic
Animals with ectoderm, endoderm, and mesoderm
Define: Mesoderm
Middle layer of the three germ layers
All bilaterians are…
a) Diploblastic
b) Autotrophic
c) Triploblastic
d) Symmetrical
c) Triploblastic
What do most triploblastic animals possess
A body cavity
What is a true body cavity called
A coelom
What are coelomates?
Animals that possess a true coelom
What two kinds of development categories can many animals be categorized as having?
Protostome
Deuterostome
Describe cleavage in Protostome development (2)
Spiral and determinate
Describe cleavage in Deuterostome development (2)
Radial and indeterminate
What three groups are Deuterostomes?
Echinoderms
Hemicordates
Chordates
Are most animals Protosomes or Deuterostomes?
Protosomes
What system is developed from the ectoderm?
The brain/nervous system
What is an acoelomate?
An animal with no body cavity separating gut and body wall
What is a pseudocoelomate?
An animal that has a body cavity but it isn’t fully lined by the mesoderm.
Which kind of development allows for the possibility of a cell breaking off in early cleavage and fully developing?
Deuterostome development
What is possible because of indeterminate cleavage?
Identical twins and embryonic stem cells
What hole comes first in Dueterostomes?
Ass
What hole comes first in Protosomes?
Mouth
What hole comes second in Deuterostomes?
Mouth
What hole comes second in Protosomes?
Bum!
How many phyla do zoologists recognize? (range)
30-40 phyla
What percent of animals are invertebrates?
95%
What kind of symmetry do Ctenophora have?
Radial symmetry
What do Ctenophores lack?
Nematocytes
How do Ctenophores expel waste?
Through anal pores
What do Ctenophores use instead of nematocytes?
Sticky filaments
What are two features of Ctenophores?
Meogla and feeding tenticles
How do Cteniphores expell their sperm and eggs?
Through their mouths
Are Ctenophores bioluminescent?
They often are
How do Ctenophores move?
By using cilia on plates
What kind of animals are sponges?
Sessile aquatic/marine animals
What do sponges lack?
True tissues and organs
What phylum are sponges
Porifera
True or False:
Most sponges are hermaphorodites
True
How do sponges feed
They suspension feed
What parts of a sponge assist with suspension feeding? (3)
Choabocytes
Osculum
Spongocoel
Describe the process of suspension feeding
Choanocystes move water through pores into the spongocoel and out through the osculum
What phylum is the oldest in the clade Eumetazoa?
Cnidaria
What clade does the phylum Cnidaria belong to?
Eumetazoa
What two forms have Cnidarians diversified into?
Sessile (polyp)
Motile (medusa)
What are three general groups of Cnidarians?
Jellies
Corals
Hydras
Describe the basic body plan of a Cnidaria
Sac with a central digestive compartment
What is the name of the central digestive compartment in Cnidarians?
Gastrovascular cavity
What is the function of the one opening on the Cnidarians?
It is a mouth and anus
How many tissue layers are present in Cnidarians?
2 layers
Are Cnidarians herbivores, omnivores, or carnivores?
Carnivores
How do Cnidarians capture prey?
With tentacles
What cells are found on the tentacles of Cnidarians and what are their 2 functions
Cnidocytes
Function in defense and capture of prey
What are nematocysts?
Specialized organelles within cnidocytes that eject a stinging thread
What kind of symmetry do Bilaterian animals have?
Bilateral symmetry
Bilaterian animals have …..blastic development
Triploblastic
What two groups fall under the clade Bilateria?
Protosomia
Deuterostomia
What two groups fall under Protosomia?
Lophotrochozoa
Ecdysozoa
What are some organisms considered to be Lophotrochozoa? (5)
Ectoprocts Brachiopoda Flatworms Molluscs The annelids
Why do some organisms develop a lophophore?
For feeding
What kind of stage do some Lophotrochozoa go through?
Trochophore larval stage
What specific feature do Lophophorates have?
A lophophore
Describe a lophophore
A horseshoe-shaped, suspension-feeding organ with ciliated tentacles
Lophophorates include
the phyla:
Ectoprocta and Brachiopoda and
others
What is another name for ectoprocts and why?
Bryozoans because they resemble plants
What kind of animals are Ectoprocts? (social + body feature)
Colonial animals encased in an exoskeleton
What do some Ectoproct species do?
Build reefs
What do Brachiopods resemble uperficially
Hinge-shelled molluscs
What sets Brachiopods apart from hinge-shelled molluscs?
They have dorsal and ventral shells rather than lateral shells
Where do Platyhelminthes live?
In marine, freshwater, and damp terrestrial habitats
Although flatworms
undergo …..
development, they
are …..
triploblastic
acoelomates
Describe flatworms
They are flattened dorso-ventrally and have a gastrovascular cavity
What are tapeworms and what do they do?
They are parasitic flatworms that lack digestive systems, requiring them to gather nutrients from a host’s intestine
What is the common name of the phylum Nemertea?
Ribbon worms
Decribe Ribbon worms (Environment, how they eat, size…)
Marine
Carnivorous
Elongate and colourful
Usually less than 20cm but have been found up to 54m long
What organisms are included in the phylum Mollusca?
Snails Slugs Oysters Clams Octopuses Squids
What environment do molluscs inhabit? (3)
Marine habitats
Some fresh water
Some terrestrial
Describe the physical body of molluscs (really unspecific)
Soft-bodied, but most are protected by a hard shell
What 3 parts make up the general body plan of molluscs?
Muscular foot
Visceral mass
Mantle
What feature is common do many molluscs have?
Water- filled mantle cavity
What structure do molluscs use to feed?
Rasp-like radula
What are the four major classes of molluscs?
Chitons
Gastropods
Bivalves
Cephalopods
What class consists of chitons?
Polyplacophora
Describe chitons
Oval shaped marine animals encased in an armor of eight dorsal plates
Roughly what portion of all living species of molluscs are gastropods?
Three quarters
About three-quarters of all
living species of molluscs are…
Gastropods
What class are bivalves?
Bivalvia
What does bivalvia mean?
Shell in two halves
What organisms are included in the class Bivalvia? (non-specific)
Clams
Oysters
Mussels
Scallops
What class are Cephalopods?
Cephalopoda
What organisms are included in the class Cephalopoda?
Squids
Nautili
Octopuses
Describe cephalopods
Carnivores with beak-like jaws surrounded by tentacles of their modified foot
Look at octopus slide
Weird wording
What kind of hooks do squid suckers have?
Chitinous hooks
Describe annelids
They have bodies composed of a series of fused rings
What three classes is the phylum Annelida divided in to?
Oligochaeta
Polychaeta
Hirudinea
What organisms are in the class:
a) Oligochatea
b) Polychaeta
c) Hirudinea
a) earthworms and their relatives
b) Polychaetes or marine worms
c) Leeches
What are Oligochatea?
Terrestrial and aquatic worms named for their bristles of chitin or chaetae
What do earworms eat and how do they extract nutrients
They eat soil, extracting nutrients as soil moves through the alimentary canal
Desricribe members of the class Polychaetes
They have paddle-like parapodia that work as gills and help with locomotion
Describe members of the class Hirudinea
Blood sucking parasites, predators, or scavangers
Secrete a chemical called hirudin to prevent blood coagulation
What are ecdysozoans covered by?
A tough coat called a cuticle
By what process is the cuticle shed or molted?
Ecdysis
What are the two largest phyla of Ecdysozoans?
Nematodes
Arthropods
What is another name for nematodes?
Roundworms
Where are nematodes found? (4)
In most aquatic habitats, soil, moist tissues of plants, and in the body tissues and fluids of animals
3 characteristics of nematodes
Internal fertilization
Alimentary canal
No circulatory system
How many living species of velvet worms are there?
65
What habitat do velvet worms inhabit
Terrestrial, moist, temperate, and tropical habitats in the southern hemisphere
What are two features of velvet worms?
They have numerous paired legs and are superficially segmented
Do velvet worms bear live young?
Yes
… out of every … species of animals are anthropods.
Two
Three
Where are members of the phylum Arthropoda found? (broad)
Nearly all habitats of the biosphere
Describe anthropods (2)
Covered in an exoskeleton made of proteins and chitin
Molt exoskeleton as they grow
What kind of circulatory system do anthropods have?
An open circulatory system
What fluid is found in the circulatory system of anthropods and where does it circulate?
Hemolymph
Circulated into the spaces surrounding the tissues and organs
What are a variety of organs specialized for in anthropods?
Gas exchange
What is the subphylum of Cheliceriforms?
Cheliceriformes
What are Cheliceriforms named for?
Claw like feeding appendages called chelicerae
Earliest cheliceriforms?
Eurypterids (sea scorpions)
Most marine cheliceriforms are … but some species survive today, including … and …
Extinct
Horseshoe crabs
Sea spiders
Most modern cheliceriforms are …
Arachnids
What are 4 examples of arachnids?
Spiders
Scorpions
Ticks
Mites
Describe the body structure of Arachnids
Abdomen
Cephalothorax
Book Lungs
Specialized abdominal glands
What are the appendages found on the cephalothorax and what are their names?
Six pairs of appendages
Chelicerae
Pedipalps
Legs
What do many spiders produce?
Silk, a liquid protein
What group of animals has mainly remained in marine and freshwater environments?
Crustaceans
What is the subphylum of Crustaceans?
Crustacea
Describe a typical crustacean
Branched appendages,
Seperate male and female parts
What do crustaceans use their branched appendages for?
Feeding and locomotion
Isopods include what three species? (non-specific)
Terrestrial
Freshwater
Marine
What is a well known group of terrestrial isopods?
Pill bugs!
What group are relatively large crustaceans?
Decapods
What are 4 examples of decapods?
Lobsters
Crabs
Crayfish
Shrimp
What subphylum includes millipedes and centipedes?
Myriapoda
Describe Myriapods
Terrestrial with jaw-like mandibles
Millipedes are … that eat decaying plant matter
Detritivores
What does each truck segment of millipedes have?
2 pairs of legs
Centipedes are what kind of heterotroph?
Carnivores
How many leg pairs do they have per trunk segments?
One pair per trunk segment
What subphylum has more species than all other life forms combined?
Hexapoda
Where do hexapoda live?
In almost every terrestrial habitat and in fresh water
What does the internal anatomy include? (non-specific)
Several complex organ systems, such as light organs
What organisms are know for their light organs????
Fireflies!!!
What are the advantages that an animal that flies has (3)
Escape predators
Find food
Disperse to new habitats much faster
What did flight allow for with respect to palnts?
Feeding o gymnosperms and co-evolution with angiosperms
What two diversity griups declined during the Cretaceous extinction?
Insect and plant
How long has insect and plant diversity been increasing?
65 million years (since the Cretaceous extinction)
Sea stars and other echinoderms are from the phylum?
Echinodermata
What phylum do Echinodermata seem to have little in common with?
The phylum Chordata, including vertebrates
Echinodermata are
a) Protosomes
b) Flagellates
c) Deuterostomes
d) Anteaters
c) Deuterostomes
Pls don’t say anteaters
Chordates share many features of embryonic development with…
Echinoderms and acorn worms
How long have Chordates been evolving seperately?
At least 500 million years
All chordates share a set of …
Derived characters
Some species of chordates only have derived character traits during what stage of development?
Embryonic development
Four key characteristics of chordates
Notochord
Dorsal, hollow nerve chord
Pharyngeal slits or clefts
Muscular, post-anal tail
What is the notochord?
A longitudinal, flexible rod made of fluid-filled cells surrounded by tough connective tissues between the digestive tube and nerve chord
What does the notochord do?
It provides skeletal supports throughout most of the length of a chordate
Do most vertebrate adults have a notochord?
No, they just retain the remnants of the embryonic notochord
What kind of skeleton forms in vertebrates with respect to chordates?
A more complex, jointed skeleton
In chordates, pharynx grooves are called … and they develop into … that …
Pharyngeal clefts
Slits
Open to the outside of the body
What are the three function of the pharyngeal slits?
Suspension-feeding structures in many invertebrate chordates – Gas exchange in vertebrates (except vertebrates with limbs, the tetrapods) – Develop into parts of the ear, head, and neck in tetrapods
What do chordates have posterior to the anus
A tail
In many species of chordates the tail is greatly reduced during …
Embryonic development
What does the chordate tail contain? (2)
Skeletal elements and muscles
What does the chordate tail do?
It provides a propelling force in many aquatic species
What are lancelets named for?
Their blade-like shape
What group do Lancelets belong to?
Cephalochordata
Describe Lancelets
Marine suspension feeders that have characteristics of the chordate body plan as adults
What is the name for invertebrate chordates?
Tunicates
Which is more closely related to other chordates, Tunicates or Lancelets?
Tunicates
When do tunicates most resemble chordates?
During their laravl stage
How long may a tunicate larval stage last?
Onl a few minutes
What form do tunicates take on after their larval stage
One of a sessil, marine suspension feeder
How do unicates eat as adults?
They filter food particles our of water which they draw in through an incurrent siphon
Fossils from the … document the transition to craniates
Cambrian explosion 530 million years ago
What are the two most primitive craniate fossils?
Haikouichthys and Myllokunmingia
What distinct characteristics do craniates possess.
a skull,
brain, eyes, and other sensory organs
What did the presence of a head allow chordates to begin to do
Hunt (active predation)
In aquatic craniates the pharyngeal clefts evolved into …
Gill slits
Craniates have a heart with …, red blood cells with … and …
At least two chambers
With hemoglobin
Kidneys
What group is the least dervived survining craniate lineage?
Myxini (hagfish)
What are characteristics of hagfish?
Hagfishes have a cartilaginous skull and axial rod
of cartilage derived from the notochord, but lack
jaws and vertebrae
During wht peiod did craniates evolve into vertebrates
Cambrian period (approx. 525 mya0
What are three dervived characteristics of vertebrates?
Vertebrae enclosing a spinal cord
An elaborate skull
Fin rays, in the aquatic forms
Approximately how many species of vertebrates are there?
52,000
What organism represents the oldest living lineage of vertebrates?
Lampreys (Petromyzontida)
Describe lampreys
Jawless vertebrates
Live in marine and freshwater habitats
Have cartilaginous segments surrounding the notochord and some of the nerve chord
Oral disk
What are Gnathostomes?
Jawed vertebrates
What percentage of vertebrates are Gnathostomes?
99%
What are two groups that are also Gnathostomes?
Placoderms
Chondrichthyans
What are 4 examples of chondricthyans?
Sharks
Skates
Rays
Chimeras
Describe a condrichthyan skeleton
They have a cartilaginous
skeleton that evolved
secondarily from an ancestral mineralized skeleton
Condricthyans are … carnivores
Mostly fast swimming
Are shark eggs fertalized externally or internally?
Internally
Oviparous
eggs hatch
outside the mother’s body
Ovoviviparous
the embryo
develops within the uterus
and is nourished by the egg
yolk
Viviparous
the embryo develops within the uterus and is nourished through a yolk sac placenta from the mother’s blood
What group of gnathostomes do most vertebrates belong to?
Osteichthyes (boney fish)
What three groups are Osteichthyes?
Bony fish
Lobefish
Tetrapods
What group are we part of (general)
Jawed boney fish
What do nearly all living osteichthyans have?
A bony endoskeleton
What are aquatic osteichthyans informally called?
Fish
How do most fish “breathe”?
by drawing water over
gills protected by an operculum
How do fish control their boyancy?
Air sac! (swim bladder)
What class are ray-finned fishes?
Class Actinopterygii
What do Actinopterygii use their fins for?
Maneuvering, defense, and other functions
What two features do Lobe-fins have?
Muscular pelvis
Pectoral fins
What three lineages of lobe-fins survived?
coelacanths (Actinistia), lungfishes (Dipnoi),
and tetrapods
What did some lobe-fins evolve?
Limbs and feet
What specific adaptations do tetrapods have? (2)
– Four limbs, and feet
with digits
– Ears for detecting airborne sounds
How many species of the class Amphibia are there?
6,150
What does amphibian mean?
Both ways of life
Amphibian … are aquatic and … are terrestrial
Larva
Adults
How are amphibian eggs fertalized and what do they require?
Externally
Require moisture
What aids amphibians in gas exchange?
Moist skin
When did amphibians and amniotes split?
About 370 mya
Describe amniotes
A group of tetrapods, more tolerant of dry conditions
What organisms are amniotes?
Reptiles, such as birds and mammals
Define: Anapsid
No holes in skull
Define: Synapspid
One hole set in skull
Define: Diapsid
Two hole sets in skull
What 7 general groups are in the reptile clade?
Tuataras Lizards Snakes Turtles Crocodilians Birds Dinosaurs
Two characteristics of reptiles
Scales that create a waterproof barrier
Shelled eggs laid on land
The oldest reptilian fossil to date is
310 mya
What was the first major group of reptiles to emerge?
Parareptiles
Describe parareptiles
Large, stocky herbivores
As parareptiles were dwindling, … were diversifying
Diapsids
What are the two main lineages of diapsids?
Lepidosaurs and archosaurs
What organisms are Lepidosaurs? (3)
Tuataras
Lizards
Snakes
What organisms are archosaurs? (4)
Crocodilians
Pterosaurs
Dinosaurs
Birds
Dinosaurs diversified into … and were …
Various shapes and sizes
Fast- moving
What group was included in the dinosaurs?
Bipedal carnivores called theropods
What group are birds?
Archosaurs
What is the major adaptation of birds?
Wings with keratin faethers
Other adaptations of birds are: (4)
lack of a urinary bladder,
females with only one
ovary, small gonads, and
loss of teeth
How long ago did birds probably descend from theropdods?
150 mya`
What is Archaeopteryx
The oldest known bird from sediments that are 150 myo
How many species of mammals are there?
5,300
All mammals have: (4)
– Mammary glands, which produce milk – A relatively large brain – Hair – Differentiated teeth
What did mammas evolve from and in what period?
Synapsids in the late Triassic period
What three living lineages of mammals emerged by the early Cretaceous
Monotremes
Marsuprials
Eutherians
“Mammals underwent a significant
adaptive radiation until after the Cretaceous”
True or false?
False
They did not
Describe monotremes
Small group of egg-laying mamals consisting of the platypus and echidnas
Describe marsupials
Mammals with develop in a placenta in a mothers uterus for a short time
Examples of marsupials (3)
Opossums
Kangaroos
Koalas
Where is embryonic development completed in marsupials?
In a maternal pouch, a marsupium
Another name for eutherians is …
Placentals
Placentals have a … pregnancy when compared to marsupials
Longer period of pregnancy
Where do eutherians complete their embryonic development?
In the uterus, joined to the mother by a placenta
