Zoology Lab practical chpters 10-14
nematodes have what type of body plan
psuedocoelemate
What are the two characteristics that arthropods have in common?
segmented bodies and jointed appendages
When did trilobites first appear? What type of digestion system did they have?
the cambrian explosion complete digestion system
Describe the crop and gizzard
the crop is where food is stored before it moves to the gizzard.
What is cephalization
the development of the head
How can you tell a male from a female in rotifers?
the males are generally smaller than the females
Parthenogenesis is?
the process of females producing only females from unfertilized diploid eggs a type of asexual reproduction
What are chromatophores?
the specialized epidermal cells called chromatophores allows them to blend in perfectly with their surroundings
What are malpighian tubes?
they are used for excreting metabolic waste
ectotherms means?
they do not generate body heat internally
How many pairs of eyes do horseshoe crabs have?
they have 2 pairs. Lateral compound eyes and simple eyes
What are annelids nervous system like?
they have a dorsal brain with two lobes and a single ventral nerve chord
Ascaris is the roundworm we dissected what kind of nerve chords do they have?
they have dorsal and ventral nerve chords
how do nematodes move?
they move by using their fluid filled body cavity and contracting the muscles against it
What is the function of the mantle?
to secrete the the protective shell
Leeches lack setae and parapodia true or false?
true
some species of rotifers only consist of females that produce more females true or false?
true; some exists as only females that produce more females from unfertilized diploid eggs a type of asexual reproduction called parthenogenesis
The folding of the intestinal wall is known as the?
typhlosole
Do nematodes have cuticles?
yes
The phylum arthropoda phylogeny
***Subphylum Tilobitomorpha*** Class-Trilobita- trilobites ***Subphylum Chelicerata*** Class Merostomata- horseshoe crabs Class Arachnida-spiders, scorpoins, ticks, mites, tarantulas ***Subphylum Myriapoda*** Class Chilopoda- centipedes Class Dipolopoda- millipedes ***Subphylum Crustacea*** Class malacostraca- crayfish, lobsters, crabs, shrimps, isopods Class Hexapoda- Class insecta- insects
what are two physical characteristics that define phyla rotifera
1. a ciliated crown technical name corona 2. a pharyngeal apparatus known as the mastax that grinds food in predatory species
the phylum mollusca is characterized by what elements?
1. a protective shell (reduced in some species) 2. a mantle 3. a visceral mass that houses the major internal organs 4. a foot for locomotion
What are the two major classes in the phyla annelida?
1. polycheata (clamworms, sandworms, fanworms) 2. Clitella (earthworms, angleworms, leeches)
How many hearts does a squid have?
3 hearts -systematic heart - 2 branchial hearts
How are pinworms transferred?
By getting under the fingernails and then being ingested
Arachnids feed mostly as?
Carnivores
What are the characteristics of phylum arthropoda- subphylum Myriapoda- class chilopoda
Centipedes -Terrestrial -cylindrical body divided into head and segmented trunk; one pair of legs per body segment; one pair of antennae poison fangs present
Characteristics of Polyplacophora?
Chitons -Dorsal shell consists of eight overlapping plates; ventral body with head foot; entirely marine
Characteristics of Bivalvia?
Clams, oysters, mussels, scallops -two part, hinged shells; reduced head; marine or freshwater filter feeders
What is the name of the heartworm?
Dirofilaria immitis
The guinea worm is is known as? and it is important because?
Dracunculus medinensis
what is detritus feeding?
Eating organic material that settles on the surface of the muddy substrate
The pinworms name is?
Enterobius vermicularis
True or False: nematodes have an excretory system, a circulatory system and respiratory system
False; they have a excretory system, however they do not have a circulatory system or respiratory system
What are the classes and their representative animals of the phylum mollusca?
Gastropoda (snails, slugs) Bivalvia (clams, oysters, mussels) Polyplacophora (Chitons) Scaphopoda (tusk shells) Cephalopoda (squids, octopuses)
What are the parts of a rotifer's body?
Head, trunk, and foot
What are the characteristics of phylum arthropoda- subphylum Chelicerate- Class merostomata
Horse shoe crabs; -marine -lack antennae and mandibles first pair of appendages are chelicerae. Second pair are pedipalps four pairs of walking legs spiked telson and platelike gill opercula present on abdomen
What kind and how many nerve chords does the earthworm have?
It has a single ventral nerve chord
What is the technical name for the typical earth worm?
Lumbricus
What is the anatomy of a horseshoe crab? And scientific name?
Merostomata limilus
name a predatory polychaete?
Nereis (sandworm)
Earthworms are?
Oligochaetes
What is the function of the The posterior adductor muscle and how can you identify it? and what is the function of the anterior adductor muscle and how you can identify it?
Posterior adductor muscle is bigger than the anterior muscle. Both of these muscles functions are to open and close the shell
Locate the prostomium, mouth, anus, clitellum, papilla, seminal groove, opening to vas deferens, openings to oviducts
Prostomium- at the anterior Mouth- located just under the prostomium
Characteristics of Gastropoda?
Snails, slugs, nudibranchs -well developed head with eyes and tentacles; body undergoes torsion during development; primarily marine, with some freshwater and terrestrial species
What are the characteristics of phylum arthropoda- subphylum Chelicerate- Class Arachnida
Spiders, scorpions, ticks, mites tarantulas -Terrestrial -Lack antennae and mandibles; first pair of appendages are chelicerae second pair of appendages are pedipalps four pairs of walking legs no abdominal appendages or telson
Characteristics of Cephalopoda?
Squids, octopuses, nautiluses -Foot modified into tentacles; shell greatly reduced; prominent head with well developed eyes and beak; closed circulatory system, entirely marine highly active predators.
What helps clam burrow and move?
The foot
What is a telson? and what is it used for?
The tail of a horseshoe crab; used to flip the harsh crab back over if it gets right side up.
Explain the blood vessels in the earthworm
There are ventral and dorsal blood vessels
How do horseshoe crabs feed?
They are primarily nocturnal and swim on their backs in search of small molluscs and worms to feed on
How do rotifers move?
They attach to a substrate they have a foot that possess adhesive glands that secrete a type of chemical cement and then they swim by means of ciliary actions of the corona
How do spiders respirate?
They have book lungs that are small slits along the ventral surface of the abdomen which allow air to enter a hollow compartment filled with nemerous thin folds of the body wall that resembles pages of a book. One side of each page is exposed to air and the inner layer of the page is bathed in hemolymph allowing gas exchange across the thin moist surface
How do oligochaetes respirate?
They use their entire epithelial surface for gas exchange
Explain sexual reproduction in the earthworms?
Tow worms align along their ventral surfaces with their heads pointing in opposite directions and secrete a slimy mucous emission from each clitellum that holds them together during copulation. Sperm are discharged simultaneously from each worm and travel to the seminal receptacles of their mate along the grooves in the ventral body surface. The worms separate and each worm secretes a mucous band from its clitellum that forms a sticky cocoon that slides forward picking up eggs from the egg sac and sperm from the seminal receptacles. Fertilization occurs within the cocoon which slips off the anterior end of the worm and is deposited near the entrance to the worms burrow. Eggs develop for two to three weeks before juvenile earthworms emerge.
Mollusca and annelids go through a distinctive larval stage called the?
Trochophore
Characteristics of Scaphopoda?
Tusk Shells -Body enclosed in one piece, curved conical shell open at both ends; mouth with tentacles, head absent entirely marine.
How does a cephalopods eye compare to a vertebrates eye?
Vertebrate eyes have an elastic lens and visual images are focused on the retina by altering the shape of the lens. Cephalopod eyes have a rigid lens and focus images on the retina by altering the distance between the lens and retina. Just like a camera. The vertebrates eye has a blindspot while the cephalapods do not have a blind spot.
How does water circulate through the mussel?
Water circulates dorsally through the mantle cavity and through the suprabranchial chambers within the gills and makes a 180 degree turn, passing along the dorsal aspect of the mantle cavity. Nitrogenous wastes are excretes by the kidney into the water as it passes. As the water leaves the clam through the more dorsal excurrent siphon, it passes directly past the anus, where wastes are eliminated from the digestive system and swiftly carried away from the animal
Arthropods nervous system consists of?
a dorsal brain and a single ventral nerve cord
What is a cephalothorax? Who has them?
a fused head and thorax Horseshoe crabs
Trichinella Spiralis
a roundworm that infects the intestines of pig hosts
What are the characteristics of phylum arthropoda- subphylum trilobitomorpha class trilobite?
all extinct; consisted of a head throat and tail
Why do animals with exoskeleton not use their coelom for locomotion?
because they are in such a rigid suit of armor. In some species the coelom has been gratefully reduced
What are setae?
biological term derived from the Latin word for "bristle". It refers to a number of different bristle- or hair-like structures on living organisms. They are found on Oligochaetes
Spiders fangs are what structure modified?
chellicirae
What is an arthropods exoskeleton made of?
chitin
Annelids have what type of circulatory system?
closed
What type of digestion system do annelids have?
complete digestive system
What type of evolution is the cephalopod eye?
convergent evolution
Nematodes are monoecious or dioecious
dioecious
Rotifera are monoecious or dioecious
dioecious
Leeches are what kind of parasite?
ectoparasites- they only attach themselves to the outside of the host organism
Blood pressure in earthworms are maintained by?
five aortic arches or hearts located in segments 7-11
vinegar eels are?
free living nematodes
Parapodia's function?
gas exchange,burrowing, walking
What is the pool of blood called in an open circulatory system?
hemolymph
nematodes have what type of skelatory system?
hydrastatic skeleton
hypodermic impregnation is a process where male rotifers..
inseminate the female by injecting sperm through the body cavity wall
What is the purpose of the gill opercula in the horseshoe crabs?
it is there to conceal the delicate book girls underneath; The purpose of it beating is that it also is there to swim and aerates the book gills https://www.youtube.com/watch?v=sCtAv7fU1lc
What is the function of the clitellum?
it is used during reproduction for transferring sperm between individuals and in secreting a cocoon that contains the fertilized eggs
Rotifera is a phyla or a class of nematode
its own phyla
Class Clitella and Subclass Hirudinea what is the animal associated with this subclass?
leeches
What are the components of the squid's eye?
lens, cornera, iris, ciliary muscles, and a retina
what kind of muscle structure do nematodes have?
longitudinal muscles
The name polychaeta refers to?
many bristles in reference to setae projecting from side flaps called parapodia
What does the term myriad pod mean?
many footed
How do the gills function in reproduction and food acquisition?
mollusks are dioecious, in female muscles eggs are fertilized within special chambers in the female as sperm cells released from nearby males are brought in by water currents. Females brood the fertilized eggs in special pouches in the gills until the eggs are ready to hatch. The eggs develop into tiny larvae called glochidia that attach to the gills of certain fish species and act as external parasitic larvae detach from the gills of the host fish and settle to the seafloor to complete their transformation.
What is ecdysis?
molting- a new exoskeleton is secreted and fixed in place before the old shell is shed
Earthworms are?
monoecious
What type of circulatory system do arthropods have?
open circulatory system
Molluscs have what type of circulatory system? And how does it work?
open circulatory system- in bivalves blood from tissues and major organs flows to the gills where it is oxygenated and is directed passively back to the heart. The blood enters through the openings in the heart called ostia and is pumped out of the heart thorough artier to the mantle foot and the visceral mass where it empties into open sinuses in the tissues of these regions small veins collect the blood and return it to the gills.