199.103 Module Two: Biodiversity

What are the three domains of life?

Bacteria, Archaea, Eukarya

Fundamental features of Bacteria

Prokaryote, contain one RNA polymerase, Lipid membrane with fatty acids

Fundamental features of Archaea

Prokaryote, contains three RNA polymerase, does not contain a bilayer instead a membrane that contains hydrocarbons

Eukaryote

A cell that contains a nucleus and membrane bound organelles, DNA is linear

Prokaryote

A unicellular organism that lacks a nucleus and membrane bound organelles

Defining characteristics of plants

Multicellular

Make their own food

Photosynthetic and contain chlorophyll which allows them to convert energy from the sun into food

Enable other life forms to exist

Defining characteristics of fungi

Multicellular , eukaryotic heterotrophs that feed by absorption

What features characterise an organism as being an animal

Multicellular, heterotrophic eukaryotes with tissues that develop from embryotic layers

Defining characteristics of sponges

multicellular, pore bearing, no organs, unsymmetrical , regeneration of body parts, no true tissues

Define the term diploblastic

Having two germ layers —used of an embryo or lower invertebrate lacking a true mesoderm.

Defining characteristics of cnidarians

diploblastic, tentacles with stinging cells (cindocytes) , gastrovascular cavity with only one opening serving as mouth and anus, radial symmetry

Defining characteristics of bilaterians

triploblastic, bilateral symmetry, a coelom (digestive tract with two openings)

explain the term triploblastic

three embryonic cell layers; ectoderm, endoderm and mesoderm

tissues that derive from ectoderm

germ layer covering embryos surface (skin, nervous system, eye, mammary glands, hair)

tissues that derive from endoderm

innermost germ layer and lines the developing of the digestive tube (digestive tract, intestines, colon, pancreas, stomach, liver, lungs, bladder)

tissues that derive from mesoderm

present in all bilateria (skeletal muscle, skeleton, heart, blood, kidneys, spleen, connective tissue, genitals)

defining characteristics of Lophotrochozoa

Triploblastic, bilaterally symmetrical

Define the term 'acoelomate'

an animal that does not possess a body cavity

defining characteristics of Platyhelminthes

Triploblastic, acoelomate, and bilaterally symmetrical. Possess a central nervous system, free living or parasites.

Provide examples of two parasitic Platyhelminthes

Flukes and Tapeworms

defining characteristics of molluscs

Three main parts; Muscular foot, visceral mass and Mantle. Soft bodied and most secrete a hard shell made of calcium carbonate.

List the names of the four major classes of molluscs

Polyplacophora (chitons)

Gastropoda (snails and slugs)

Bivalvia (clams, oysters, and other bivalves)

Cephalopoda (squids, octopuses, cuttlefish, and chambered nautiluses).

Major features of Polyplacophora (chitons)

oval-shaped marine animals encased in an armour of eight dorsal plates

Major features of Gastropoda (snails and slugs)

Most have a single, spiraled shell that functions in protection from injury, dehydration, and predation

Major features of Bivalvia (clams, oysters, and other bivalves)

They have a shell divided into two halves drawn together by adductor muscles. Mantle cavity which contains gills which are used for feeding and gas exchange

Major features of Cephalopoda (squids, octopuses, cuttlefish, and chambered nautiluses).

Beaklike jaws which inject poison into prey, closed circulatory system, well-developed sense organs, complex brain, mouth found centre of tentacles under muscular foot/head

defining characteristics of annelids

coelomate, triploblastic, bilaterally symmetrical, body is segmented

List two clades of annelids

Errantia and Sedentaria

Explain the functioning of the excretory system of an earthworm

Excretory system consists of nephridia as excretory organ which functions like the kidney in vertebrates

defining characteristics ecdysozoans

Cuticle; a tough but flexible exoskeleton

List six phyla of ecdysozoans

Arthropoda, Panarthropoda, Kinorhyncha, Priapulida, Loricifera, Nematoda, and Nematomorpha

defining characteristics of nematodes (round worms)

cylindrical in shape, tissue level organisation, body contains a cavity, canal is distinct with a mouth and anus, cuticle, non-segmented

defining characteristics of arthropods

exoskeleton (chitin), jointed limbs, segmented body, nervous system, bilateral symmetry

List features that arthropods share with their annelid-like ancestors

Segmentation

Nervous system

One way gut

Both small invertebrates

Explain how arthropods grow and the structure of their exoskeleton

Growth is solved in arthropods by molting, or ecdysis, the periodic shedding of the old exoskeleton. Enzymes break the old exoskeleton and it gets secreted with a new one

discuss distinctive features and provide examples of high-level diversity amongst the arthropods

Insecta (flight, rapid reproduction, increased variation)

Crustaceans (calcium carbonate exoskeleton, antennae)

List features that have contributed to the extraordinary success of the arthropods

evolution of flight, exoskeleton, jointed limbs, simple and adaptable body plan

Define Protostomes

"First Mouth"; animals that develop the mouth first, then the anus as embryos

Define Deuterostomes

organisms in which the first opening to form in the embryo becomes the anus

defining characteristics of echinoderms (star fish)

water vascular system (hydraulic canals branching into tube feet), star-like, marine animals, skeleton made up of calcium carbonate

scientific and common names for the five extant clades of echinoderms

Crinoidea (sea lilies)

Asteroidea (starfish)

Ophiuroidea (brittle or snake stars)

Echinoidea (sea urchins)

Holothuroidea (sea cucumbers)

Describe how sea stars move and feed

Sea stars use suction in their tube feet for movement and feeding

defining characteristics of chordates

Notochord, dorsal hollow nerve cord, pharyngeal slits, post-anal tail

Explain what a notochord is

Flexible rod formed of a material similar to cartilage, main structural support

Define 'vertebrate'

A possession of a backbone or spinal column

Distinguish between hagfishes and lampreys

Lampreys are true vertebrates (having a notochord and better skeleton) , hagfishes are not

Define 'gnathostome'

Jawed vertebrates

Specify the major structural component of the skeleton in chondrichthyans and give common names for representative taxa within this group

Cartilage (sharks, rays and skates)

scientific names for bony-finned fishes and lobe-finned fishes

Ray finned fish = Actinopterygii

Lobe finned fish = Sarcopterygii

Explain what an osteichthyan is and specify which major groups of animals fall within this taxon

Bony fish that have skeletons primarily composed of bone tissue (cartilaginous fishes, bony fish and tetrapods)

Name the major taxonomic groups of reptile

Testudines (turtles and tortoises),

Rhynchocephalia (the tuatara from New Zealand)

Squamata (lizards, snakes, and worm lizards)

Crocodilia (crocodiles, gharials, caimans, and alligators)

defining characteristics of the clade tetrapoda

four limbs, adaptions to skeleton that enable them to live on land, head is supported

defining characteristics of the clade Amniota

amniotic egg (allows them to lay eggs on land)

Describe how the derived characters of the tetrapods reflects the change from aquatic toterrestrial life

Amniotic egg, adaptations in gas exchange (ribs) , keratinised skin, pelvis is more robust

What are the three orders of Amphibian

Anura (frogs)

Caudata (salamanders)

Gymnophiona (caecilians)

defining characteristics of Anura

tailless and have strong hind legs

defining characteristics of Caudata

long slender bodies with tails, four limbs are more evenly sized

defining characteristics of Gymnophiona

limbless

Outline the reproductive strategies of amphibians

Reproduce sexually, do not produce amniotic eggs so must reproduce in water, larvae go through metamorphosis to change into adult form

Describe how amphibian respiration differs from that of other tetrapod groups

early life they use gills, develop lungs, additionally can breathe through their

Define synapsid

single pair of lateral temporal skull openings

Define Diapsid

two temporal openings in the skull

Give the names of the major groups of past and present reptiles

Archosaurs, Lepidosaurs, Pterosaurs, Dinosaurs, Turtles, Crocodilians

Archosaurs - two skull openings

Reptiles have legs that sprawl out to the side. Their thigh bones are almost parallel to the ground (run in side to side motion).

Dinosaurs stand with their legs positioned directly under their bodies.

Defining characteristics of birds

Wings with keratin feathers, High metabolic rate/ warm bloodedness, Upright posture, Large brain size, No urinary bladder

Describe how the anatomy of birds reflects their ability to fly

Hollow but strong bones

Air sacs

Keratin feathers

No urinary bladder

Only one ovary

One way respiratory system

Recall the inherited reptilian and derived avian characters of Archaeopteryx

Had a full set of teeth like reptiles and a long tail.

Presence of feathers, wings arrangements similar to birds

Describe how the muscles and bones of the avian pectoral girdle interact to move birds'wings

Fused collarbones

Keeled breastbone which acts as an attachment site for muscles involved in flight

(Pectoralis: muscle pulls wing down and Supracoracoideus: muscle raises wing up)

Describe how avian respiration differs from groups with tidal ventilation

Birds lungs do not expand or contract instead they have relatively small lungs and air sacs that allow more oxygen to be available to diffuse into the blood

Give the names of the major groups of extant mammals and describe their key differences

Monotremes- lays eggs

Marsupials- completes embryo development in an external pouch

Placentals- completes embryo development inside the mother

Defining characteristics of mammals

Hair, Mammary Glands (Milk for young)

Describe how mammals ventilate their lungs

Pulmonary ventilation = air gets inhaled through the nasal cavity, gets warmed, trachea funnels the inhaled air to the lungs and the exhaled air out of the body.

Describe how jaw articulation and hearing changed in the evolution of the synapsids

Existing jaw bones become incorporated into the inner ear

Recall the relationships among the apes

Share a common ancestor Hominidae

defining characteristics of humans

Large brain

Bipedal locomotion

Shorter digestive tract

Reduced jaw bones and jaw muscles

Upright posture

Name key hominin lineages and recall any important developments associated with thosespecies

Homo sapiens - symbolic and sophisticated thought

Homo erectus - human- like body proportions, cooking

Neanderthal - tool makers, had culture, buried their dead

Proglottids

ribbon of sex organs

Which bone was important for jaw movement in the earliest synapsids but is now used for hearing in living synapsids?

quadrate

What traits do all animals in the clade Vertebrata share

Neural crest tissue