Practical Notes Flashcards
What are acoelomates?
Animals that have no body cavity. The infernal organs have direct contact with the epithelium. Semi-solid mesodermal tissues between the gut and body wall hold their body together.
What are pseudocoelomate animals?
They have a pseudcoel which means they have a false cavity because It is not made within the mesoderm nor does It end fully enclosed by mesoderm. Also organs in it are not as fully organized as in a real coelomate.
What are eucolomate animals?
They are animals with a true coelom (body cavity). True coeloms may be either fluid or gas filled; they provide protection and support for internal organs as well as more space in which organs can develop . Animals with coeloms have a faster locomotion and larger body size.
Characteristics of a platyhelmithes
Bilaterally symmetrical body usually flattened dorsoventrally
Triploblastic (three tissues)
The gut (if present) has a single opening
There is a definitive head with sense organs and a central nerve system
Excretion by flame-cells
Complete digestive track no anus
Many parasitic.
Characteristics of class Turbellaria
Free-living and primarly carnivorous
Mostly freshwater, few marine and terrestrial
Body is dorso-ventrally flattened
No anus and mouth on ventral side
Locomotion using cilia which are on the ventral side on the epidermis. They Also move by muscular movements.
Characteristics of dugesia
Freshwater
Intestine 3 primary branches
Locomotion vía cilia and secreted mucus from mucus cells in epidermis
LEARNING DIAGRAM
What are some main differences between sponges and dugesia ?
Sponges are asymmetrical and dugesia has a bilateral symmetry.
Sponges have a cellular organisation and dugesia have an organ organisation.
Sponges don’t have any cephalisation and dugesia has a definitive head.
How does dugesia feeds?
It attaches mouth to its prey, releases digestive enzymes, sucks digested tissues and vomits the waste because It doesn’t have an anus.
Characteristics of platyhelmithes
Always parasitic
2 hosts ( at least one vertebrate)
Hermophroditic - individual segments with reproductive system released to environment.
No gut system -absorb nutrients straight across body surface
Attachment to organs
Characteristics of dipellyium sp.
Parasitic tapeworm in dogs
In the development stages their host its an invertebrate
Consists on a head called scolex, a neck and a series of segments called proglottids (new proglottids produced on head region )
Mature proglottids contain male and female reproductive organs.
Sperm from a tapeworm will fertilise the egg of the same or another tapeworm.
The mature proglottids will burst open to release the zygotes which are released in the feaces of the host which then are consumed by a new host and the cycle continues.
LEARN THE DIAGRAM of SCOLEX
How dipyllidium caninum feeds?
They are normally attached to the intestines and they absorb the nutrients that arrive from the stomach.
Why the scolex of the Dipyllidium not considered a true head?
Doesn’t have the organs that characterize a head.
How does a mature proglottids looks like?
Examine diagram in practical
Compare dugesia and dipyllidium
Dugesia definitive head- dipyllidium scolex
Dugesia and dipyllidium both hermaphrodites
Digestive system present on dugesia and not in dipyllidium
Characteristics of trematoda
Parasitic
Highly complex life cycles
Blind gut
Sporocyst within snail host
Characteristics of fasciola hepiteca
Parasite that infects many species of animals.
Largest flukes - 3.5 by 1.5cm
Live in liver or bile duct
Found in 46 sp
Intermediate host - Lymnea snail
In adult stage they have a large leaf-shaped body
Examine DIAGRAM
Characteristics of phylum nematoda
Triploblastic
Have a pseudocoelem
Bilaterally symmetrical
Complete digestive track with two openings ( mouth and anus)
Thick cuticle and under it longitudinal muscles
Lack circular muscle and their muscle is limited ti a thrashing motion
Mostly dioceious
How cam you differentiatte males from females nematodes?
Their reproductive features
The openings they have
The bigger one is a female
And the shape
Locomotion of nematodes
They move in an S form one part of their body contracts while the other relaxes pushing It forward
An example of an Aecoelomate?
Fasciola hepatica :look at DIAGRAM
The mesoderm takes up more space in acoelomates
An example of pseudocoelomates?
Ascaris sp : look at DIAGRAM
In the pseudocoelomates the mesoderm doesn’t occupy as much space as in acoelomates because as pseudocoelomates need to process more food therefore they have a larger intestines track and less mesoderm .
Main characteristics of Phylum mollusca
They have a reduced coelem Dorsal visceral mass Mantle A broad ventral foot Have a radula to feed And a shell for protection
Mollusca foot in the different classes of molluscs
Gastropoda: its located in its ventral part and It is large and flat.
Polyplachora: It is located in its ventral part and It is large , flat and strong.
Bivalvia: In the center and use for digginng ( bigger the foot= more movement)
Chephalopoda: located in the anterior part and It is modified Intro tentacles use to grab food.
The molluscan mantle
Gastropoda: located dorsal part under the shell, It can wrap around shell.
Polyplacophora: runs down both sides in the ventral cavity and secreted plates and houses gills.
Bivalvia: inside and besides the shell, secretes valves(shell) , home for zooxanthallae.
Cephalopoda: located in the dorsal part, outside shell and cover shell, mantle cavity used for locomotion in water
What are some functions of the molluscan mantle ?
Create the shell
Rap organs
Carry respiratory organs
Molluscan shell
Gastropoda: dorsal and one side thin while the other is thick.
Polyplacophora: dorsal and It has 8 valves.
Bivalvia: 2 shells hinged
Cephalopoda: dorsal and inside the body, large chambered shell, reduced in octopuses
How is an gastropod shell?
Look at DIAGRAM .
How is a shell in bivalves?
Look at the DIAGRAM
What are Molluscan radula ?
Rasp-like belt positioned over a tongue-like structure with rows of teeth.
Characteristics of bivalves
Second largest class of mollucs Lack a head and a radula
Why does the mantle is attached to the outer edge of the shell?
To secrete shell to both sides and for more protection.
Why is the foot reduced in mussels?
They don’t move that much= smaller foot.
How is the bivalve inside ?
Examine DIAGRAM
Main characteristics of annelida
Segmented bodies
Each segment contain a a pair of nephridua, a ganglios and a locomotory structure
Have circular and longitudinal muscles surrounded by a moist flexible cuticle.
All have chitinous hair-like structures called chaetae ( except leeches)
Main characteristics of class Polychaeta
Segmented worms that range in size from 1mm to 4m
Each segment has a pair of highly vascularised parapodia (used for locomotion)
What is the function of parapodia of Nereis sp. ?
It is used for locomotion .
Would you expect a polycheate that lives in a tube to have larger or smaller parapodia?
It is smaller because its easier to move inside a tube than through sediment . Examine DIAGRAM of parapodium.
Main characteristics of oligochaeta
Water-based skeleton ir hydrostatic skeleton used for locomotion
Have some hair/ chaetae
What is one main characteristic of bilateria?
At some stage in their development all these animals are bilaterally symmetrical.
How does the body of Nereis sp. Differ from an earthworm?
They have parapodium and the earthworm doesn’t
Head is very define and complex and earthworm is simple
Few chaetae -earthworm has many
They don’t have a reproductive structure.
Which muscles cause the earthworm to lenghthen and which muscles cause the earthworm to contract?
Contracts circular muscles and relaxes them and then he contracts the tube muscles to get longer and then It continues to walk.
Main characteristics of class hirudinea
Shorter body than polychaetes and oligochaetes and fewer segments (34 typically)
Annuli make the body to appear more segmented
Coelom significantly reduce
No septa
How is the locomotion in leeches?
They contract and use their suckers to attach to the floor then they relax their muscles go totally flat and repeat the process.
Compare and contrast annelidS
Polychaeta: head well developed, present appendages, abundant cheatae and no clitelum
Olichaeta: poorly developed head, no present appendages, few chaetae, present clitellum.
Hirudinea: obvious head, no present appendages, no chaetae, no clitellum.
Characteristics of class chelicerata
Mouth parts chelicerae ( pincers or fangs)
Pedipalps present
No antenae
4 pairs of legs
2 body regions ( cephalothorax and abdomen)
Respiration variable (gills ,book lungs, book gills or thachea)
Main characteristics of Myrapodia
Mouthparts are mandibles One pair of antennae 2 body regions ( head and trunk) Paired uniramous appendages Trachea
Main characteristics of hexapoda
Mouthparts are mandibles 3 pairs of legs May have wings 3 body regions ( head, thorax, abdomen) One pair of antennae Respiration via trachea or spiracle (variable )
Main characteristics of class Crustacea
Mouthparts are mandibles Appendages are biramous Number of legs (highly variable ) Two pairs of antennae 2 or 3 body regions ( cephalothorax and abdomen) Gills
Comparasion between annelids and arthropods
Annelids: have a coelomate, triploblastic, bilateral symmetry, segmented bodies, hydrostatic skeleton, don’t molt, appendages present only in polychaetes.
Arthropods : open circulatory system, bilateral symmetry , secreted exoskeleton, they molt, have jointed appendages and they metamerism.
How is the body of a horseshoe crab?
See DIAGRAM
Differences between scorpion, tick and spider
Scorpion : 2 segments , abdomen is in segments, have chelicerae to tear prey apart, their pedipalps modified to chelae prey capture, 8 legs, 6-12 eyes, spinnerets absent, antennae absent, mandibles present.
Tick: 2 segments ( cephalothorax and abdomen) , their chelicerae cuts through skin so tick can extract blood, their pedipalps grasp skin, 8 legs, 1-5 eyes, no spinnerets , no antennae, no mandibles
Spider: 2 body parts ( cephalothorax and abdomen), their chelicerae are fangs that inject venom and paralyse prey, their pedipalps manipulate food, 8 legs, 8 eyes, spinnerets present (produce silk) , absent antennae , present mandibles
Comparasion between milipedes and centipedes
Centipedes: 15-117 body sections, 2 mallipedes (they are like claws) , 1 pair of legs per segment, 2 pairs of antennae ( one in head another jointed) , present eyes, spiracles located in third segment.
Milipedes : 100-1000 body sections, 1 mallipede, they have mandibles , 2 legs per segment, one pair of antennae ( in the head and jointed), present eyes, spiracles near the top of legs slightely dorsal .
Comparasion between green ant, cricket and moth
Ant: 3 body sections (head, thorax and abdomen , has mandibles( Sharp and two destroy food), 6 legs located in thorax ( no chelate), no wings, one pair of antennae (jointed), present eyes (oscillae) , spiracles in abdomen.
Cricket: 3 body sections (head, thorax , abdomen), has mandibles (smaller and thinner than ants), 6 legs in thorax ( no chelate), one pair of wings located in thorax , one pair of antennae (not jointed ), one pair of eyes, spiracles in abdomen.
Moth: 3 body sections ( head , y hora and abdomen , has a siphon (modified mandibles), 6 legs in thorax , no chelate , one pair of antennae ( not jointed) , one pair of wings in thorax , pair of eyes , spiracles in abdomen.
Locomotion in ants, crickets,
Cockroach
Cricket: can walk slowly using all their legs, hop using larger legs.
Ants: move fast using all their legs and can walk in the glass.
Cockroach: Run fast using all their legs.
How crickets feed?
Crickets just move head up and down , use mandibles to break food, sense food with antenae, maybe use legs to grab food.
Comparasion between prawn and crab
Prawn: 4 sections ( head, thorax , abdomen and telson), 3 pairs of mastillepedes, have maxilla which pushes food to mouth , 5 pairs of walking legs, 5 pairs of swimming legs, gills above walking legs, one pair of antennae not jointed , one pair of eyes present.
Crab: 3 sections (head, thorax and abdomen), maxillepeds and maxilla , 7 legs and two claws, gills located in thorax, 2 pairs of antennae , one pair of eyes
Locomotion and feeding of stomatopod
They flick their tails to move and with front legs are used for the hard surface .
They have spear like barbs on their raptural appendages( used them to reach fishes as they walk)
What are the four characteristics of chordates?
- A notochord
- A dorsal hollow nerve
- Pharyngeal gills.
- The post anal tail
Main characteristics of class asteroidea
Marine Small endoskeleton Calcareous plates bond together by connective tissue Radial pentamerous symmetry No head or brain Water vascular system
How is the body of a starfish?
See DIAGRAM
Describe the flow of water in the vascular system
Madreporite, stone canal, ring canal, radial canal , lateral canal , ampullae, tube feet.
How does the arm of asteroidea looks like ?
See DIAGRAM
What is the function of pedicellaria?
They are used to capture food,they keep body surface without algae and encrusting to organisms.
General morphology in echinoderms
Asteroidea : 5 arms, central mouth, pedicellaria present, Spines in some, ambulacral grooves in arms and in oral surface , small tube feet with suckers, grabs food with arms and mouth leads to stomach which is everted when feeding .
Ophiuroidea: 5 arms (thin),distinct central disc, mouth facing substrate, Spines along arms (thin and Sharp, help for locomotion and protection) , closed ambulacral groove, tube feet located oral part of the brittles in the arms, push food to mouth, some are suspension feeders and scavengers.
Crinoidea: tentacles up with mucus to grab food, Mouth is not facing the substrate, no present Spines , closed ambulacral groove, tubes have mucus and are along tentacles .
General morphology of echinoderms 2
holothuroidea: cylindrical form, have a braching tree for respiration, tentacles at the top, mouth an anus opposite of substrate, have tube feet all along the body and Oral tentacles (modified tube feet)
Echinoidea: circular (sphere/ elliptical), pentamerous symmetry, separate sexes, upward position of mouth, Spines throughout all of the body ( used for locomotion and protection , big) , open ambulacral groove, tube feet used for feeding and in some for locomotion , use aristotle’s lantern ( 5 teeth) to feed.
In what do vertebrates differ from other chordate groups?
- A distinct head and the brain is enclosed in a protective case.
- Vertebral column (replaces the notochord during embryonic development)
Importance of a vertebral column
The backbone provides support and protection to the dorsol hollow cord , It also provides muscle attachment .
Made up of repeating units called vertebrae.
In many species they are shock -absorbing discs between the vertebrae to cushion them during movement.
Importance of vertebrate endoskeleton
Made of bone or cartilage.
Cartilage= tough tissue that contains protein called collagen.
Bone= hard tissue that consists of a collagen matrix filled with minerals such as calcium. Bone is less flexible than cartilage but stronger. Animals can grow larger and heavier with a bone exoskeleton.
What does an axial skeleton consists of ?
Skull, ear bones, vertebral column and ribs.
It forma the central axis of the body .
What does the appendicular skeleton consists of ?
Pectoral girdle, the limbs, the pelvic girdle and lower limbs.
Main characteristics of sharks
External morphology: gill openings, mouth with Sharp teeth, no axial or axis, males have dospers and females don’t.
Fin: two dorsal fin, two pelvic fin and one anal fin.
Skin: countless overlapping scales, grooves running down their lenghthen in aligment to water . Skin is irregular.
Dentitation: highly modified skin located in the area of the mouth.
Skeleton : made of cartilage, has vertebral column, mandible arch ( jaws), branchial arches (gills).
Locomotion : pectoral find conrotate and use the trunk and cadual to move.
Main characteristics of fish
Externas morphology: separate in two (trunk and caudal), gill cover , mouth + nostrils, highly variable morphology.
Fins: dorsal fin, pectoral fin, pelvic fin anal fin, adipose fin and caudal fin .
Skin: ray finned fish - skin with mucus glande and scales , some have ganoid scales , others have cycloid scales and other ctenoid scales. Some fish have “naked” skin.
Dentition: depending on its diet the dentation changes.
Skeleton : in rayed fish- cartilage or bone and they have a vertebrae.
Locomotion : some move in anguilform (like eels) and other move in thunniform ( like tuna)
Main characteristics of amphibians
External morphology : frog-eyes, nostril, head, tympanum, front and hind legs, belly, webbed foot, web trunk, metamorphosis from tadpole to adult. Salamander-four limbs and a tail. Caealiar-long, slender, legless, no limbs.
Skin: frogs- epidermis and dermis, poison gland , mucous glands, chromatophores. Salamander- moist skin without scales.
Dentition: acrodant( attached on the inner surface of the jawbome), hondonat(all teeth are functionaly and anatomicaly the same)
Skeleton: frog-skull, cervical vertebrae (atlas) , trunk vertebrae, single sacral vertebrae and urostyle vertebrae.
Locomotion : jumping, climbing, gliding, burrowing, swimming .
Caealiars: move by muscles contractions with segmented bodies.
Main characteristics of reptiles
External morphology : lung-breathing vertebrals, two pairs of limbs, legs of reptiles shifted to the bottom of the body.
Skin: horny, scaly skin which is dry which allows them to move around large periods without water.
Dentition: komodo-ferocious bite, cocodrile- sharp go along jaws , turtles have a beak .
Skeleton : cervical vertebrae, thoracic vertebrae, sacral vertebrae and caudal vertebrae.
Locomotion: swimming , bipedal locomotion, flying (gliding ) , walk and climb
Main characteristics of birds
External morphology : eyes, nostril, beak, wings covered with feathers, claws , ears, tail feather, metatarsus
Skin: thin , delicate and clothed in feathers(created by keratin)
Dentition: they have a beak (made up of keratin ) , beak varies depending on diet.
Skeleton: pectoral girdle made up of sternum, clavicle, corocoid and scapula. Pelvic girdle made up of fusion of bones in pelvic region.
Locomotion: flying , walking with two claws
Main characteristics of mammals
External morphology : have ears, 4 legs, some of them have a tail , hairy, have two eyes , one nose.
Skin: most mammals have hair.
Dentition: varies depending diet of animal.
Skeleton: corucal vertebrae, thoracic vertebrae, lumbar vertebrae, sacrum, caudal vertebrae.
Locomotion : walk, trotting, leaping, crawling, hopping, branchiatum (moving from branch to branch), swimming and flying.
