Download - Biodiversity Part 2/2
KINGDOM ANIMALIACharacteristics
Multicellular Eukaryotic organisms Exhibit heterotrophic nutrition Have nervous coordination and muscular system (for respond quickly to
environmental stimuli) except for sponges Extraordinarily diverse in their shape and functions Most can reproduce sexually, and are invertebrates (without backbone) Only 1% of this kingdom is vertebrates
(I) Phylum Porifera (Sponges)
Sessile (means fixed permanently in one place) Mainly marine organisms which filter feed by passing a current of water through pores in
their bodies Doesn’t have nervous coordination and muscular system like animals Commonly shaped like a vase Shape varies with the direction and force of water currents Unique body water canal system which for filter feeding Asymmetrical body (No regular body shape) Reproduce asexually because of its high capacity for regeneration Has 3 classes : Calcarea, Hexactinellida, Demospongiae
Structure of sponges
1. Spongoecoel central cavity of sponge2. Body perforated with holes or spores called as ostia3. The body consists of 2 layers of cells separated by gelatinous protein-rich region mesohyl4. The outer layer made up of epidermal/epithelial cells, the cells are modified to form
porocytes which control size of pores and regulate water flow5. Inner layer made up of collar cells/choanocytes (specialised flagellated cells) 6. Mesohyl contains amoebocytes which function for: digestion(phagocytosis), transportation,
secretion of spicule (fine needle CaCO3), production of reproductive cells
Sexual Reproduction of Sponges
Normally the sponges will reproduce asexually, but some can reproduce sexually. This is because of Amoebocytes can produce male and female gametes but at different time. The egg will remain in mesohyl but the sperms are carried out by water currents. The fertilisation will occur in mesohyl and zygote develops into free-swimming larva.
Class Calcarea Hexatinellida Demospongiae
Feature CaCO3
spicules Large
choanocytes
Six-Rayed Spicules
Small choanocytes
Variable skeleton (spongin fibres/silica spicules or both)
Small, round choanocytes
Example Sycon , Euplectella , Cliona ,
Leucosolenia Hyalonema Euspongia
(II) Phylum Cnidarian
are diploidblastics (means has 2 cell layers which are endoderm and ectoderm, both are separated by gel-like layer called as mesogloea)
have nematoblasts (stinging cells) radially symmetrical have tentacles
have nerve cells that interconnect with contractile(muscle) and gland cells possess both reproduction: 1. Asexualbudding and regeneration
2. Sexualgamete production and fertilisation
Structure of Cnidarians
1. cell layers which are endoderm and ectoderm, both are separated by gel-like layer called as mesogloea
2. Cnidocytes which contain nematocyst(capsule) which has nematoblasts within it. Located abundantly in outer epidermis)
3. When a cnidocil is triggered, the nematocyst is discharged and paralyse/kills the prey or predator (like pushing recoil of gun for firing)
4. Extracellular digestion, inner cell layers secrete enzymes to digest food partially in gastrovascular cavity(enteron) and the digested food particles taken up by endodermal cells by endocytosis
5. Flagellated endodermal cells help to circulate nutrients inside the enteron 6. Undigested material expelled through mouth which also functions as anal7. SHAPE OF BASIC BODY : can be POLYP, MEDUSA, or POLYMORPHIC(both)
1.Polyp Shape2.Medusa Shape
Class Hydrozoa Scyphozoa Anthozoa
Characteristics 1. Mostly marine and colonial
2. Polymorphic
3. Marine4. Medusa
5. Marine6. Polyp
Example 7. Hydra, Obelia Aurelia (jellyfish) 8. Sea anemone
picture above showing an example of Hydrozoa: Obelia and its life cycle
III) Phylum Platyhelminths (flatworms)
1. Are flat, unsegmented, bilaterally symmetrical (only single line/plane that divide the body into equal halves)
2. Are triploblastic (has 3 layers: ectoderm, endoderm, mesoderm)3. Have mouth except cestodes, but no anus4. Usually hermaphrodites (has both male and female organs) with
complex reproductive system5. Acoelamate which means without coelom2nd body cavity6. Has 3 classes: Turbellaria, Trematoda And Monogenea, Cestoda
Class Turbellaria Trematoda And Monogenea
Cestoda
Characteristics
Free-living Ciliated
body surface
Typically carnivorous
Enteron present
Simple life history
Parasitic Posseses
suckers for attachment to host
Enteron present
Complex life history
Parasites of vertebrae
Enteron absent Complex life
history
Examples Planaria Liver fluke Fasiola
Tapeworm(Taenia)
Structure Of Planaria
Its head at its anterior end with pair of simple eyes Has chemoreceptors on lateral lobes Has clearly defined CNS –central nervous system Its braindense clusters of nerve cells , connected with a pair of nerve
cords Together, both sensory organs and nerves made up nervous system
LIFE CYCLE OF TAENIA(TAPEWORM)
Firstly, the mature proglottids will be expelled along with faeces (in Chinese: 粪)
SECONDLY, THE EGGS (WHICH PRODUCED BY PROGLOTTID) INGESTED BY INTERMEDIATE HOST (EXP.COW) WHEN CONSUMING CONTAMINATED VEGETATION
THEN, INSIDE THE GUT, THE EGG WILL HATCH INTO HOOKED LARVA AND TRANSPORTED INTO THE BLOOD SYSTEM
EVENTUALLY THE LARVA WILL TRAVEL TO THE MUSCLE TISSUE AND THE CYCLE IS COMPLETED WITH FORMING CYSTICERCI ..
HOWEVER, IN HUMAN, THE CYSTICERCI WILL DEVELOP IN 2 MONTHS, AND RESIDE INSIDE THE SMALL INTESTINE BY USING THEIR SCOLEX (HOOK),BECOMING MATURE TAPEWORMS AND LIFE CYCLE IS COMPLETED.
IV) Phylum Nematoda ( Roundworms )
Triploblastic Bilaterally-symmetrical Have unsegmented bodylack of coelom Pseudocoelamate Have mouth and anus Don’t have cilia and flagella Have separate sexes Life cycle as same as Taenia(tapeworm) Have 2 classes: Aphasmida, Phasmida
Class Aphasmida Phasmida
Presence of phasmid - √
Development of Excretory System
Poor Well
No. of copulatory Spicules
1 2
Example Trichuris, Capillaria Ascaris, Ancylostoma, Wuchereria
Diagram below shows an exp. From Phasmida, wuchereria which causes elephantiasis
Growth of Ascaris lumbricoides
V) Phylum Annelida ( Segmented Worm )
Triploblastic Bilaterally symmetrical Have metameric segmentation for facilitate locomotion and modification into different
organs Have repeating units called segments which separated by septa, and with paired chaeta
/setae Has 3 classes: Oligochaeta, Polychaeta, Hirudinea
Class Oligochaeta Polychaeta Hirudinea
Characteristics
few chaetae per segment
Non-Distinct head
Live in freshwater or damp earth
Lots of chaetae per segment
Distinct head
Live in marine
No chaetae Non-Distinct head Normally live in
freshwater ectoparasitic
Examples Lumbricus (earthworm)
Nereis (ragworm)
Hirudo (medicinal leech)
Structure Of Annelids
1. 3 types of body cavity: Acoelomate, Eucoelomate, Pseudocoelomate
2. Posseses coelom in fluid-filled form which helps to i)act as hydrostatic skeleton
ii)provide space for emplacement and enlargement of internal organs, product storage
iii)allow body and alimentary canal operate independently
iv)may act as circulatory medium
3. Have digestive system pharnyx, oesophagus, crop, gizzard, intestine4. Have circulatory system blood vessels(pump)contain haemogoblin5. Have excretory system funnel-shaped tubules called nephridia
remove waste and eliminate them through pores in the body wall
VI) Phylum Anthropoda (segmented appendages + exoskeleton)
Triploblastic Bilaterally-symmetrical segmented Chitinous exoskeleton Display high degree of cephalisation Has open circulatory system (like spm, ostia and haemocoel(spaces) Gaseous exchange in 1.aquatic anthropod (gills)
2.normally insect (tracheal tubes)
3.terestial anthropod (book lungs)
WHY ANTHROPODS ARE MOST SUCCESSFUL AMONG ANIMALS??
Because of:
1. strong, rigid exoskeleton2. various locomotion3. mouth adaptation for obtaining variety of foods4. High reproductive capacity 5. Metamorphosis life cycle reduces the competition in population6. Have diverse defensive mechanism exp. Stinger, poison claw, camouflage7. Has 6 major classes: Insecta, Arachinda, Crustacea, Chilopoda, Diplopoda, Merostomata
Effects Of Anthropods On Human Activites
POSITIVE biological control, pollination, nutrient recycle, provide food source(zooplankton) for fishes
NEGATIVEdisease vector, pest to algricultural crops, food spoilage, building/clothes damage
CLASS INSECTA Most got 2 pairs of wings attached to thr]oracic segment, but some convert wings to
balancing organs (halteres) Its life cycle characterised by several moults, gap between 2 moults called instar Holometabolous insect possesses complete metamorphosis Hemimetabolous insect possesses incomplete metamorphosis In complete metamorphosis, there are 4 distinct stages : egglarvapupaimago In incomplete metamorphosis, there are 4 distinct stages too:
eggnymphinstaradult Example of hemimetabolous insect: Periplaneta Americana(cockroach)[ORDER
DICTYOPHERA]
CLASS ARACHNIDA Has no antennae (but its function replaced by numerous sensory hairs around body 2 body parts composed by cephalothorax(head+thorax not separated), and abdomen Has 1 pair of appendages(palps), 1 pair for capturing prey, and 4 pairs for walking Example: Spider which belongs to order Araneida , diagram below showing anatomy of
spider without legs and Scropion; The anterior and small appendages can be modified into poison fangs, pincers called as
Chelicera
stucture/anatomy of Scorpion
(based on resources from http://webs.lander.edu/rsfox/rsfoximages3/scorpion40La_x550_x_503x.gif)
CLASS CRUSTACEA Have cephalothorax Have 2 pairs of antenna, 3 pairs of jaws, 5 pairs for walking, 5 pairs for swimming Lack waterproof exoskeleton (that’s why when prawn is soaked inside spices, it absorbs the
flavour of spices too)
Normally carry its fertilised egg inside its body. The egg will follow hemimorphosis Example : Penaeus (prawns) [ORDER DECAPODA]
CLASS CHILOPODA normally refer to centipedes1. Carnivorous 2. Have distinct head3. Have 1 pair of antenna
1 pair of jaws
4. Similar legs along body length, one pair each segment5. Example: Lithobius
CLASS DIPLOPODA normally refer to millipedes1. Herbivorous2. Have 1 pair of antenna and jaws; as same as chilopoda3. Numerous similar limbs along body length, 2 pairs per segment4. Example : lulus or 火车虫
CLASS MEROSTOMATANormally the species within this class are in extinction, however, we should learn it when we have a chance..
There are 3 only genera in this class, called as HORSESHOE CRABS
They possess cephalothorax and abdomen to form hard shell Their growth based on Hemimorphosis by shedding its skin ,grow larger and larger The cephalothorax bears 6 pairs of appendages, chelirae and 4 pairs of legs EXAMPLE: LIMULUS WHICH CAN BE FOUND IN NORTH AMERICA
VII) Phylum Mollusca
Coelomate animals 2nd largest in animal phylum Have soft body which covered by shell Normally CaCo3 shell/Calcareous shell secreted by epidermal shell (mantle)-which also
houses gills, anus, and excretory pores Outward segmented body Possesses radula(chitinous teeth) to scrap food and drill holes of prey’s shell Have open circulatory system Excretory system carried out by nephridia(tubule) Most have separate sexes External fertilisation
Have 3 classes Of Mollusca:
Class Gastropoda Pelycopoda CephalopodaSymmetry
Asymmetrical Bilaterally symmetrical
Bilaterally symmetrical
Shell type
Coiled Flattened internal/external/no shell
Presence of radula
present absent because they are filter feeders
present along with horny beak
Example Helix (snail) Mytilus, Ostrea
Octopus
Pictures
VIII) Phylum Echinodermata
Marine mammals with 5-way radial symmetry Have water vascular system connected with numerous tube feet ;which help for
locomotion, respiration, and feeding Possess endoskeleton which composed by Ca plates called as ossicles Can reproduce both asexually and asexually but separate sexes and external fertilisation Example: Starfish
There are 5 major classes in phylum Echinodermata:
Class Characteristics ExampleCrinoidea Mouth, anus faced
upwards Suckerless tube feet
Sea lilies Feather stars
Asteroidea Pentagonal shape Sucker tube feet
Starfish
Ophiuroidea Star-shaped with slender branched arms
Suckerless tube feet
Brittle stars
Echinoidea Similar arms Tube feet sticked out
from endoskeleton
Sea urchin
Holothuroidea Armless Cylindrical shape Few,small ossicles Tube feettentacles
around mouth
Sea cucumber (Holothuria)
IX) Phylum Chordata
has notochord (rod of ventilated tissue) has nerve cords, tail, pharyngeal gill slits (connect pharynx and oesophagus with
outside/respiratory openings) One of the subphylum called ‘vertebrata’ is distinguished from chordates due to possession
of vertebral column (bone/cartilage + distinct head) Bilaterally symmetrical Metamerically segmented Triploblastic coelamates There are 6 major classes which are: Chrondrichthyes, Osteichthyes, Amphibia, Reptilia,
Aves, and Mammalia
Class Chrondrichthyes1. Have a soft,flexible skeleton made of cartilage2. Ventral mouth3. Flesh fins4. Have gills with separate openings5. Skin contains dermal denticles/placoid scalestooth-like structures with
enamel(outer)layer and dentine(inner) layer 6. Typically have heterocercal tail dorsal lobe tail fin is > than ventral lobe7. Possess lateral line which is enriched with sensory cells for detection
Class Osteichthyes1. Have skeleton made of bone
2. Have fins supported by bony or cartilaginous rays3. Its gills covered with a bony flap (Operculum)4. Usually have skin with scales5. Have homocercal tail dorsal lobe tail fin = ventral lobe6. Have swim bladders(modified air sacs) to regulate buoyancy
Class Amphibia Have 4 limbs Adult has lungs for breathing in drier environment Has soft, moist and water-permeable skin for gaseous exchange Their life cycle including aquatic larva stages with gills Has 3-chambered heart (2A 1V) OR closed, imcomplete double circulatory system EXAMPLE: rana (frog)
STRUCTURE and CHARACTERISTICS OF RANA
1. Smooth, moist skin2. Has long hind leghigh jumping ability just like grasshopper3. Webbed feet adapted for water movement4. Has transparent eyelid(nictitating membrane)5. External fertilisation6. The fertilised egg will hatch into tadpoles and grow into adult(frog) eventually. However,
tadpole and frog acts differently from morphology, physiology and behaviour. That’s why frog belongs to Class Amphibia which means ‘2 lives’…
A LOGICAL QUESTION: Why frog only can fertilise its eggs in water instead of in land?
ANSWER: because due to the water-permeable membrane of the eggs, it will undergoing dessication by presence of air and eggs just like facing high temperature in microwave..
Class Reptilia Produce leathery amniotic eggs in shells to allow embryo develops within its aqueous
environment Dry, scaly skin which made up of keratin, watertight properties Has 3-chambered heart with partial septum helps to reduce mixing of bloods Normally have pendatactyl limbs which just like human’s hand bones, but this excluding
snakes… Ectothermicwhich makes reptilian become or continue to be strong, healthy, and
successful in warm climates compared to cold climate EXAMPLE: crocodiles, naja (cobra), lizard, snake
Characteristics of Snake [ORDER SQUAMATA)
1. does not have limbs but replaced with >200 ribs for movement2. scaled ventrally
3. fork-shaped tongue4. loose-fitting jaws for enable to swallow preys that are larger than its mouth5. has paired copulatory organs/gonads in male
diagram below shows anatomy of snake:
CLASS Aves Before, they have 2 pairs of limbs but one of them modified to form wings 4-chambered heart (2A 2V), or double complete circulatory system Produces amniotic eggs with shells Have feathers,lower legs full of scales Do not have teeth but beak (every shape of beak are modifies due to their daily food
feeding) Body composed of light bones, reduced number of organs to reduce , and well-developed
breast muscle Example, Columba(pigeon) , Hirundo (swallow)
External features of Columba
Class Mammalia Have mammary glands Has four limbs, facing downward from body Have keratinised hairs which helps for 1.insulate against heat loss
2.sensory receptors
3.camourflage
Endothermiccan regulate their own body temperature to be adapted in enviroments Have heterodont dentition(means different shapes and sizes of teeth due to the diet/food
they are consuming) There 3 orders in Mammalia 1. Marsupials (pouched) exp. Kangaroo
2. Monotremes (egg-layed) exp. Platypus
3. Eustarians (uterus) exp. Human, Pan (chimpanzee)
Diagram below shows one of the example of mammals, Rattus (ORDER RODENTIA)
Pan (chimpanzee)
↑kangaroo