Gametes

·        a haploid reproductive cell, such as an egg or a sperm. Gametes unite during sexual reproduction to produce a diploid zygote.

Zygote

·        the diploid cell produced by the union of haploid gametes during fertilization; a fertilized egg

Blastula

a hollow ball of cells that marks the end of the cleavage development in animals.

Gastrula

cup shaped multicellular stage where tissue layers form.

Radial cleavage

(simplest organisms) fertilized egg divides evenly and cells aligned one above the other, ancestral state.

Spiral cleavage

egg divides evenly, planes of cell division diagonally to the vertical axis of the embryo.

Diploblastic

two layers; an outer ectoderm, and an inner endoderm

Ectoderm

the outermost of the three primary germ layers in animals embryos; gives rise to the outer covering and in some phyla, the nervous system, inner ear and lens of eye.

Endoderm

the innermost of the three primary germ layers in animal embryos; lines the archenteron and gives rise to the liver, pancreas, lungs and the lining of the digestive tract in species that have these structures.

Triploblastic

·        three layers; ectoderm, endoderm, and mesoderm that lies between.  (complex animals)

Deuterstomes

the anus develops from the blastopore, and the mouth forms after.

Radial body plans

·        a body shape with many equal parts radiating outward.  EX: cnidarians and Echinoderms

Bilateral symmetry

a body shape with a central longitudinal plane that divides the body in two equal but opposite halves.

Acoelomates

animals that lacks an internal, fluid filled body cavity (e.g.: flatworms)

Pseudocoelomates

·        animal that has an internal fluid filled body cavity that is partially filled with mesoderm tissue. (e.g.) round worm)

Coelomates

animal that has an internal fluid filled body cavity that is completely lined with mesoderm tissue (e.g. earthworms and mammals)

Motile

animals that can move around

Sessile

animals that stay in one place, they are typical filter feeders and expend energy by making water move (e.g. bryozoans)

Direct development

newborns closely resemble adult organisms. (human “babies”)

Metamorphosis

·        radical changes between larval and adult forms (butterflies)

Filter feeders

capture small organisms delivered to them by the environment.

Herbivores

·        gain energy by eating plants/ expend energy trying to digest plant material that they have eaten.

Predators

·        gain energy by eating animals/ expand energy by capturing and subduing prey. (some use toxic chemicals ex. Snakes)

Parasites

animals that live or on other animals.  Some feed on their host while others take food away from their hosts.

Endoparasites

o   live inside their hosts (tapeworms, roundworms)

Ectoparasites

live outside their hosts (ticks, lice)

Detrivores

Obtain their energy by feeding on decomposing organic matter (detritus)

·        Diploblastic animals:

Sponges

simplest animals, no distinct tissue layer, no distinct organs, feed on food particles suspended in the air, water passes through the body, most are hermaphrodites, have specialized cells:

o   Choanocytes (collar cells)

o   Resemble choanoflagellates

o   Spicules (structure)

 Spongin (collagen protein)

Diploblastic animals:

Placozoans

Diploblastic animals

Eumetazoans

o   Ctenophores- comb jellies, radial symmetry, use cilia for locomotion, sticky mucus secretion to capture prey.

o   Cnidarians have gastrovascular cavity in lieu of a gut, radial symmetry, polyp and medusa stage (adult form)

o   Bilaterians (triploblastic)

• Lophotrochozoans

(have a U or O shaped feeding structure called the lophophore) (trochophore- larval for that uses cilia for locomotion)

Lophotrochozoans:

Bryozoans

colonial animals that live in a “house” made of material excreted by the body wall, mostly marine, asexual and sexual reproduction.

Lophotrochozoans:

Platyhelminths

- flat from top to bottom (flatworms): tripoblastic, acoelomate, bilaterally symmetrical animals, most parasitic, two way digestive system, flattened for diffusion of oxygen and carbon dioxide.

Lophotrochozoans:

Rotifers

Lophotrochozoans:

Nemerteans

(ribbon worms): tripoblastic, acoelomate, bilateraly symmetry, mostly marine, feed by hollow, muscular proboscis, mouth and anus digestive tract, first evolved closed circulatory system.

Lophotrochozoans:

Phoronidans

(tube worm) triploblastic, coelomate, bilaterally symmetrical, tube dwelling marine worms, (chitin), extend lophophore from the tube to feed

Lophotrochozoans:

Brachiopods

superficially resemble clams, halves are dorsal and ventral, not lateral, tripoblastic, coelomate, bilaterally symmetrical, lophophore is inside shell, plain of symmetry is perpendicular.

KINGDOM:Lophotrochozoans:

PHYLUM: Annelids (segmented worms):

CLASS: Oligochaetes:

worms with chetae (bristles made of chitin- gives them traction), e.g. earthworms, important decomposers

-       Aerate soils

 -       Hermaphrodites

 -       clitellum

KINGDOM:Lophotrochozoans:

PHYLUM: Annelids(segmented worms):

CLASS: polychaetes:

worms with parapodia on each body segment used for locomotion and/or gas exchange, mostly marine, burrowing animals, can control the parapodia (legs) to move easier.

KINGDOM:Lophotrochozoans:

PHYLUM: Annelids(segmented worms):

CLASS: leeches:

KINGDOM:Lophotrochozoans:

PHYLUM: Molluska:

KINGDOM:Lophotrochozoans:

PHYLUM: Molluska:

CLASS: chitons:

 eight overlapping calcareous plates, radula

KINGDOM:Lophotrochozoans:

PHYLUM: Molluska:

CLASS: bivalves:

KINGDOM:Lophotrochozoans:

PHYLUM: Molluska:

CLASS: gastropods:

snails, slugs, nudibranchs (sea slugs), limpets

KINGDOM:Lophotrochozoans:

PHYLUM: Molluska:

CLASS: cephalopods:

(ceph means head) squid, octopus, nautilus

KINGDOM: Ecdysozoans:

exoskeleton or cuticle (chitin), molting must occur for an organism to grow (instar: development stages that allows them to grow), three marine groups have relatively few species: priapulids, kinorhynchs, loriciferans

KINGDOM:Ecdysozoans:

PHYLUM: Priapulids 

cylindrical, worm-like animals (not segmented), proboscis (feeding appendage), trunk, caudal appendage (tail) for locomotion.

KINGDOM:Ecdysozoans:

PHYLUM:  Khinorhynchs:

mircoscopic animasl that live in marine sediments, 13 body apendagees, retractable proboscis (typical tongue), detritivores

KINGDOM:Ecdysozoans:

PHYLUM:Loriciferans:

microscopic animals that live in coarse marine sediments

·        discovered in 1983

·        head, neck, thorax, abdomen

·        six plates

KINGDOM:Ecdysozoans:

PHYLUM:Nematodes:

(round worms) tripoblastic, pseudocoelimate, bilateral symmetry, cuticle that sheds four times, longitudinal muscles only (moves side to side only), digestive system: mouth to anus

·  free living or parasitic

·  parasitic round worms cause many diseases in plants and animals: elephantiasis, trichinosis, hear worm (dog’s diseases)

KINGDOM:Ecdysozoans:

PHYLUM:Arthropoda (joined appendages):

KINGDOM:Ecdysozoans:

PHYLUM:Arthropoda (ancestors):

 ·        Velvet worms- unjointed appendages

·        Tardigrades (water bears)- dormant state when dry

·        Trilobites- first jointed appendages (extinct)

KINGDOM: Ecdysozoans

PHYLUM: Anthropoda

CLASS: Myriapods

Order: Centipedes:

dorsoventrally flattened, one pair of legs per body segment, predatory animals, carnivorous animals.

KINGDOM: Ecdysozoans

PHYLUM: Anthropoda

CLASS: Myriapods

Order: Millipedes:

not dorsoventrally flattened, have fused segmens, so each segment has two pairs of legs (fused together), most scavengers, after decayed matter.

KINGDOM: Ecdysozoans

PHYLUM: Anthropoda

CLASS: Chelicerates

(chelicerae- piercing feeding appendages) spiders, mites, ticks, scorpions, harvestmen, horseshoe crabs , two body segments, four pairs of walking legs

KINGDOM: Ecdysozoans

PHYLUM: Anthropoda

CLASS: Crustaceans:

shrimp, crabs, lobsters, crayfish, barnacles

• ·        Cephalothorax- head and thorax fused
• ·        Appendages have many different functions- antennae, chewing mandibles, walking, gas exchange
• ·        Terrestrial crustaceans (dirt)

KINGDOM: Ecdysozoans

PHYLUM: Anthropoda

CLASS: Hexpods (insects) 

Most species rich group of all animals

Terrestrial and freshwater (very few marine)

        Evolution of flight

        Pollinators aided radiation of angiosperms

Metamorphosis

        Incomplete- nymphs resemble adults

        Complete- nymphs look much different from adults

blastopore develops into the anus, and the mouth forms later in embryotic development, exhibit radial symmetry (e.g. sea stars) or bilateral symmetry (e.g. mammals)

All are triploblastic coelomates

All experience radial cleavage

All contain an internal skeleton (internal support structure)

have bilaterally symmetrical larval form, but exhibit radial symmetry as adults – pentaradial symmetry

Have no head region-

     Oral side: side containing the mouth

     Aboral (away from mouth) side: side containing the anus

     Have calcified plates that fuse together to form an endoskeleton

     Have a unique water vascular system

                -locomotion

                -gas exchange

                -feeding  

Class Crinodea- feather stars, sea lillies

Class Echinoidea- sea urchins, sand dollars
Class Holothuroidea- sea cucumbers

Class Asteroidea- sea stars

Class Ophiuroidea- brittle stars

Hemichordates:

Acorn worms and pterobranchs have a worm-like body organized in three parts: proboscis, collar, trunk

Live in burrows

Pharyngeal gill slits (for gas exchange)

Muscular pharynx

Chordates:

All chordates exhibit the following four characteristics during some stage of their development

        -Pharyngeal gill slits

        -Post-anal tail

        -Notochord

        -Dorsal hollow nerve cord

• Lancelets
• Occur in marine and brackish sediments
• Filter feeders
• Sessile (but swim occasionally)
• e.g. Amphioxus

Urochordates:

• Ascidians- Tunicates (sea squirts)
• Occur in marine environments
• Sessile adults are filter feeders
• Free swimming (tadpole- like) larvae

• Looks like sponges “free” swimming larvae

Vertebrates:

A vertebral column replaces the notochord in early development

Evolved in a marine environment

Now are marine, freshwater, terrestrial and even aerial

Vertebrate groups:

Agnathans

(a-without/ nath- jaw)

- jawless fishes- have circular mouths with rasping tongues

- hagfish- produce slime as a defense mechanism, weak circulatory system (closed), no jaws,no stomach, can change sex from year to year

- Lampreyes- no jaws, rudimentary vertabrae (cartilage), mostly parasitic, mostly freashwater, seve gill slits.

Vertebrate groups

gnathostomes:

-Vertebrates that have jaws

-The evolution of jaws improved feeding efficiency

-Jaws and teeth make it easier to capture, subdue, and swallow prey

-Acanthodians and placoderms are the earliest jawed fishes, but are now extinct

Chondrichthyans:

- Sharks, skates, rays ratfishes and chimeras

- Cartilaginous skeleton

- Sharks maintain buoyancy by storing oils in their liver

- Streamlined bodies with paired fins

- Ampulla of Lorenzini- electrochemical receptors concentrated around the head and along the sides of the body (lateral line)

- Male sharks have claspers used for internal fertilization

- Oviparous: lay eggs that hatch externally

- Ovoviviparous: fertilized eggs mature and hatch in the oviduct

- Viviparous: young develop in the uterus and receive nutrients through a placenta

Osteichthyans:

(divided into two classes)

-Bony fishes: have an ossified endoskeleton (bone)

-Operculum: a protective bony flap that covers and protects the gills

-Swim bladder: an air sac used to maintain buoyancy

-Lateral line: row of tiny pits on either side of the body that sense movement in the water.

First osteichthyans class:

-Actinopterygii- ray finned fishes, 30,000 species, originated in fresh water, then colonized marine habitats (some anadromous(spawn in freah water) species), exploit almost any imaginable food source

Second osteichthyans class:

-Sarcopterygii- lobe finned fishes

-Coelacanth- living fossil

- Lungfish- tetrapod ancestor

Tetrapods:

Phylum: tetrapods

Class: Amphibia

 -frogs, salamanders and caecillians,

-closely tied to aquatic environments: aquatic larval form (tadpole), even if adult live in terrestrial habitats

-some secrete poisonous mucous

-many rely on their moist skin for gas exchange (secondary gas exchange)

Tetrapods- Amniotes:

development of amniotic egg

-named for the major derived character of the clade; the amniotic egg (adaptation for the terrestrial life)

-most amniotes have less permeable ski to reduce water loss, and an elevated stance for easier locomotion

calcareous shell protects against desiccation

        calcareous shell: shell with calcium

allantois: disposal sac for metabolic wastes produced by the embryo

amnion: protects the embryo in a fluid filled cavity

chorion: membrane involved in gas exchange

yolk sac: contains a stockpile of nutrients to be used by developing embryo

Tetrapods- reptiles:

-Reptiles include lizards, snakes, crocodilians, tuatara, turtles, and birds (avian reptiles)

- Scales create a waterproof barrier that helps prevent dehydration

- also prevent breathing thought skin so most reptiles rely on lungs

-Mostly ectothermic (except birds, which are endothermic)

- Adapted to life in many different environments

Reptiles:

Anapsids:

turtles and tortoises

(a/napsids= no opening “behind the eye”) skulls have no openings by the temples, all turtles and tortoises have a boxlike shell that is fused to the vertebrae, ribs and clavicle, side necked, vertical necked , live in the desert, marine environments, or ponds and rivers, most are omnivores that eat a variety of aquatic plants and animals

Reptiles:

Diapsids:

crocodilians, archosaurs, birds

Diapsids; have a pair of holes on each side of the skull, behind the eye socket

-two main lineages:

- lepidosaurs- tuatara, lizards, and snakes

- archosaurs- crocodilians, dinosaurs and pterosaurs

Lepidosaurs:

Tuatara- living fossil found on islands off the coast of New Zealand

Lizards- most diverse groups of reptiles alive today (except birds); most are small bodied, but some are large carnivores (e.g. komodo dragon)

Snakes- legless carnivores, some have chemical receptors or heat detecting organs to find prey.

Archosaurs:

Crocodilians- the only living archosaurs – alligatiors and crocodiles

Dinosaurs- most were ectotherms, but some were endotherms –mass extinction 65 mya

Pterosaurs- first tertrapods to fly, t their wings were completely different from those of birds or bats.

Birds:

“class” aves, have many adaptations for flight

ADAPTATION FOR FLIGHT:

-feathers

-wings

-reduced gonads

-hollow bones

-flow though lungs (one way)

·        Birds (Archaeopteryx):

Many fossils unearthed in China since the late 1990s have yeailed insight into bird evolution

Feathers evolved before powered flight

        -courtship

        -insulation

        -camouflage

Mammals: (class mammalia)

·        Synapsids (one opening in the eye)- mammals and mammal-like reptiles; have one hole behind the ear

Mammals underwent an adaptive radiation after the mass extinction of the dinosaurs

·        Characteristics of mammals:

• Mammary glands-produce milk or offspring
• Hair-for protection and insulation
• Four chambered heart- completely separates oxygenated and deoxygenated blood
• Sweat glands- used for evaporative cooling
• Differentiated teeth

Mammals:

sub class: prototheria:

monotremes:

-Platypus and echidnas
-Australia and New Zealand

Lack nipples, but still produce milk that young lap up of the mother’s stomach hair

Mammals:

sub class:theria:

Infraclass metatheria:  

Marsupials

-born very early in development, then completely develop in a maternal pouch

-nipples provide milk for young

-e.g. opossums, kangaroos, and koalas

Mammals: sub class: theria: Infraclass Eutheria: placental mammals (true mammals)

-embryonic development occurs inside the uterus, connected to the mother by a placenta

-filled a wide variety of ecological niches left open when the dinosaurs died off

Order primates (includes humans):

Eutherian primates radiated from a small, arboreal, insectivorous mammal /two main clades: prosimians and anthropoids

Major adaptations:

-grasping limbs

-opposable digits

-binocular vision

Family hominidae:

Hominids- bipedal locomotion

         -elevates the head

         -less energy than quadrupedal locomotion

        -allows forelimbs to carry other objects while walking

Early Hominids

Humans ancestors originated in Arica

Australopithecus (Lucy):

-first hominid discovered

-lived in Africa 4-5 mya

Homo erectus:

-first hominid to leave Africa (went to Asia)

-used fire for cooking and hunting

Homo habilus:

-used tools to obtain food

Homo sapiens:

-Brain size increased as hominids evolved

-extra brain capacity allowed for the evolution of complex language and culture

-allowed for the domestication of plants and animals

-agriculture allowed for an increasingly sedentary lifestyle

        -formation of cities

        -occupational specialization

How do ectotherms and endotherms regulate body temperatures?

Ectoderm: animals whose body temp are determined by the external environment
Endotherms: animals who regulate their body temperature.
Heterotherms: animals that switch (temperature change)

consists of sheets of tightly connected epithelial cells

      Some act as barriers:

          -skin and mucus membranes

          -lining of stomach

      Some act as filters allowing transport

          -lining of lungs and intestines

          -olfactory receptors and taste buds

Animal tissues:Muscle

(skeletal, smooth, and cardiac)

Skeletal: responsible for locomotion and other body movements

Smooth (auto pilot): responsible for involuntary generations of forces “diaphragm”

Cardiac: responsible for the beating of the heart and umping of blood strongest, constantly moving)  

Animal tissues: nervous

(neurons, glial cells)

Neurons: cells that encode information as electrical signals, and transmit them over distances to communicate to other cells.

Glial: nervous systems cells that do not conduct action potentials, but support neurons.

Animal tissues: connective (adipose, cartilage, bone, blood)

Populations of cells embedded in an extracellular matrix

Adipose: fat cells (disposal)

Cartilage: found above the ear and nose

Bone: bone marrow represents the connective parts.

Blood: connects the body and it transports proteins and nutrients.

Ectoderm:

- Lower metabolic rate

- regulate body temp. but behaviorally

- some by conserving metabolic heat

Endotherms:

Endotherms: animals that regulate their body temperature.

        -reg. temp by physiologically (controlling blood flow to skin) or behaviorally (move to cooler or warmer locations)

        - Metabolic rate is correlated with body size.

        - elevated body temps. are effective to combat pathogens (control) e.g. fever, hypothermia, hyperthermia (too hot)