Bio Exam 3 - Animal Diversity

heterotrophic - animals derive energy (carbon) from others

Multicellular - extracellular matrix including collagen

Cells are organized into tissues - groups of cells with similar structure and function bound together

fertilized egg, has genes from both parents and is first step in development

divides eggs

divides fewer cells until gastrula is formed, hollow ball of cells

organizes and defines germ layer, transfers nutrients, start gastrulation

begins tissue layer, a ball within a ball

creates three embryonic tissue layers, and creates a digestive tube

stores food so organism can transfer to adult

produces larvae into adult with drastic changes

shared derived characteristics that evolved in a common ancestor and are present in all descendants - blastula, gastrulation, mesoderms

First fossil evidence of multicellular animals - 565-550 million years ago

Diversification of animal types, forerunners of most extant phyla, bizarre body types that have since disappeared - 535 - 525 million years ago

700-800 million years ago

contains best records we have of Cambrian fossils

radial: body arranged around a central axis.

bilateral: body can be divided in near identical halves along a single plane

bilateral: Cephalization, left and right mirror images, dorsal, ventral. anterior, posterior, proximal, distal

radial: oral, aboral, proximal, distal

the concentration of sense organs, nervous control, etc., at the anterior end of the body, forming a head and brain, both during evolution and in the course of an embryo's development.

diploblastic: 2 germ layers (endoderm and ectoderm), cnidaria

triploblastic: 3 germ layers (endoderm, mesoderm, ectoderm), most other animals

endoderm: gut, liver, lungs

mesoderm: skeleton, muscle, kidney, heart, blood

ectoderm: skin, nervous system

mollusks, annelids, arthropods, echinoderms, chordates

roundworms

flatworms

a. acoelomate.

b. pseudocoelomate

c. coelomate

cleavage: protostome is spiral and determinate, deuterostome is radial and indeterminate

coelom formation: protostome is schizoccoelous, deuterostome is enteroccoelous

fate of blastopore: protostome: mouth develops from it, deuterostomes: anus develops from it

spiral/determinate: fate determined early

radial/indeterminate: fate determined late

All animals share common ancestor

Sponges (Porifera) are basal

Eumetazoans are a single clade (true tissue layers)

Most animals are bilateral (echinoderms secondarily radial)

Chordates and echinoderms are deuterostomia

parazoans, 1 phylum, sponges, filter feeding

eumetazoans, diploblastic, have forms of polyp and medusa, include medusazoans (jellyfish), and anthozoans (coral and sea anemones)

eumatazoans, comb jellies, diploblastic, plankton species, similar stinging cells to cnidaria

polyp and medusa, has alternation of generations, can be used for anti aging

corals, anemones, hard/soft corals, coral and zooxanthella symbiosis

protostomia, deuterostomia

lophotrochozoans, ecdysozoans

most diverse animals, include: mollusks, segmented worms, flatworms, named from lophophore feeding structure, and trochophore larvae stage

hard exoskeleton, grow by molting, arthropoda, Nematoda (round worms)

Platyhelminthes: flat worms, triploblastic, coelomate, planaria and parasites

Mollusca: snails, bivalves, cephalopods, diverse body plan, visceral mass, mantle, foot, diverse

Annelida: segmented worms, triploblastic, true coelom, Polychaeta and oligochaetes, repeated segments with specialization

segmented worms, triploblastic, true coelom, Polychaeta and oligochaetes, repeated segments with specialization

snails, bivalves, cephalopods, diverse body plan, visceral mass, mantle, foot, most diverse in form and habitats: Gastropoda, bivalvia, cephalopoda, and more like chitins

flat worms, triploblastic, coelomate, planaria and parasites

external cuticle or exoskeleton, three major groups: Nematoda, arthropoda, other phyla, most species rich group: crustaceans and insects. Ecdysis named for molting

round worms, triploblastic, pseudocoelomate, soil dwelling & parasitic, microscopic, diverse, trichinella parasite causes parasitic worm disease trichinosis

jointed legs, includes insects, arachnids, crustaceans, myriapods. very diverse - insects on land and freshwater, and crustaceans in salt and freshwater. most species rich phylum

include echinodermata and chordata

spiny skin, 5 groups: sea stars (starfish), brittle stars, sea urchins/sand dollars, crinoids, sea cucumbers

notochord, dorsal hollow nerve cord, pharyngeal slits or clefts, muscular post anal tail, thyroid

diverged during Cambrian explosion (540 million years ago), contain 52000 species, diverse and successful

have ‘second mouth’ where blastopore becomes anus, mouth develops secondarily from another opening

shared derived characters

shared ancestral characters

basis for endoskeleton, flexible rod

extends length of the body throughout embryonic development

originally for filter feeding, modified into gill slits for respiration, becomes structures of head and neck for many vertebrates

chordates have tail extending beyond anus, some lose tail during development (like frogs and humans)

chordates with a skull, includes: myxini (hagfishes), and all vertebrates

craniates with a backbone, includes: Cephalaspidomorphi (jawless fishes)

vertebrates with jaws, includes: extinct placoderms, Chondrichthyes (sharks and rays with placoid scales), and ourselves

chordates are defined by the 5 characteristics, craniates are a subgroup of chordates characterized by presence of skull and brain, and vertebrates are a subgroup of craniates defined by having a vertebral column or backbone. all vertebrates are craniates and all craniates are chordates, but not all chordates are craniates or vertebrates.

chordates: notochord, dorsal hollow nerve cord, pharyngeal slits or clefts, muscular post anal tail, thyroid. EX: lancelet

craniates: head with skull and brain, neural crest, HOX genes. EX: myxini

vertebrates: vertebral column, neural crest cells form bones, cranium

have cartilaginous skeleton, contain spiral valve that increases feeding efficiency in a short intestinal tract. Have a variety of reproductive strategies: oviparous, ovoviviparous, and viviparous

bony fish, but also have a complete mineralization of their skeleton (skeleton made of bone, instead of cartilage).

Synapomorphies: swim bladder, scales, bony opercurlum to protect gills

ex: salmon, tuna, bass, trout

Lobe-finned fishes (coelacanths) are the sister group to tetrapods.

four limbs with digits (can be altered or lost), lungs (to adapt to land)

Osteichthyes with limbs and feet

two part lifecycle (water and land), other variations

Lungless salamanders have direct development

Newts have a 3 part life cycle

Axolotls & tiger salamanders undergo paedomorphosis

tetrapods with terrestrial eggs, allow gas exchange for embryos

lobe-finned fishes and lungfishes

two amniote groups diverged early:

reptile (crocodiles, snakes, birds, dinosaur ancestors)

and Mammalia and their ancestors

allows eggs to be placed on land, allows gas exchange for embryos while preventing dessication

ancestral deuterostome, notochord, brain, head, vertebral column, jaws/mineralized skeleton, lung & lung derivatives, lobed fins, legs, amniotic egg, milk.

organisms: echinodermata, Urochordata, lancelets, hagfishes, lampreys, chondrichytes, ray-finned fishes, coelacanth, lungfishes, amphibians, reptiles, mammals

mammary glands, hair, three bones in ear, warm blooded

rodentia: mice, rats, squirrels

Chiroptera: bats

primates: humans, apes, monkeys

Carnivora: cats, dogs, bears

Cetacea: whales, dolphins, porpoises

A synapsid is a type of vertebrate characterized by having a single temporal opening on each side of the skull.

monotremes: lay eggs

marsupials: give birth to undeveloped young, raise in pouches

Eutherian: placental mammal give birth to fully developed young

Humans are great apes/apes, and share a common ancestor with chimpanzees 6-8 million years ago. Other great apes: orangutans, gorillas, and chimpanzees/bonobos

homo genus, these species have similar body plans to modern humans, including a larger brain size, bipedalism, and adaptations for tool use.

bipedalism, human traits (large brain, reduced teeth and jaw)

cell coordination, resource allocation, waste removal, reproduction, homeostasis

Cells, Tissue, Organs, Organ System, Organism

Tissues: Groups of cells of similar function and Appearance

(only organization in sponges)

Organs: Functional Groups of Tissues that perform a specific Function

Organ Systems: Groups of organs that accomplish a major function of regulation

epithelial tissue: surface of body

connective tissue: supports and connects tissues and organs in body (bone, cartilage, blood)

Muscular Tissue: movement and mechanical work

nervous tissue: communication and coordination in body

ability for organism to maintain a stable internal environment despite changes in external environment - regulation

regulators control and maintain a constant internal temperature regardless of changing environment, while conformers allow internal body temperature to change in response to changing environment

negative feedback reduces stimulus to keep system stable (ex: heat-sweat-evaporative cooling) while positive feedback amplifies stimuli, which does not help homeostasis (ex: population growth, childbirth)

homeostasis because despite a changing environment, these organisms need to maintain an internal temperature to survive. feedback systems are crucial in helping thermoregulation, for example: shivering and sweating. Form function and behavior can help thermoregulation: thick fur, blubber, larger animals lose heat slower, and physical grouping of animals

metabolic processes produces heat, body uses energy for thermoregulation through processes like shivering, sweating, panting, and movements

basal metabolic rate - like SMR, but under more strict conditions like after sleeping, no exercise, etc

standard metabolic rate - rate of energy consumption of an organism under standardized/variable conditions (rested, fasting, thermoneutral)

Endotherm - body heat derived from metabolism

Ectotherm - body heat derived from environment

Homeotherm - body temperature remains constant

Poiklotherm - body temperature fluctuates with environment

Hibernation is a long-term state of reduced metabolism and lowered body temperature that some animals enter during the winter months when food is scarce. Torpor, on the other hand, is a short-term state of reduced metabolism and body temperature that some animals enter during times when food is temporarily scarce, such as during the night.

external energy, essential nutrients (6): water, carbs, fats, proteins, minerals, vitamins

carnivores - commonly predators, eat other animals

Herbivores - eat plants

omnivores - eat both

proteins: growth, tissue repair, enzyme and hormone production

Carbohydrates: primary source of energy

Lipids: fats help absorb vitamins, produces hormones, maintains healthy cell membranes

Vitamins and minerals: supports immune system, maintains healthy bones, convert food to energy

ingestion: getting food into alimentary canal, alternative: filter feeding in whales and some fish, filter food particles from water

digestion: breaking down food into small enough molecules, alternative: extracellular digestion where enzymes are secreted outside organism’s cells to break down food used by insects, spiders, and some invertebrates

absorption: cells take up molecules, alternative: direct absorption, nutrients absorbed through skin in some amphibians

elimination: spelling undigested material, alternative: storage, waste products stored in body until ready to be eliminated in some insects and reptiles

filter feeding: take small particles out of water or air, mainly whales, clams, flamingos

substrate feeding: feeds on material it is in contact with, mainly earthworms, termites, leafcutter ants

fluid feeding: feed on liquids, like blood or nectar, mainly mosquitos, ticks, hummingbirds

bulk feeding: ingest large amounts of food, mainly humans, lions, Venus flytraps

Mouth: saliva helps break down food in mouth

Salivary gland: produces saliva

esophagus: muscular tube that carries food from the mouth to the stomach

stomach: mixes and grinds food, also secretes digestive enzyme pepsin

pancreas: produces digestive enzymes like amylase, lipase, etc that go to small intestine

liver: produces bile, helps breakdown fats and aids in absorption of fat soluble vitamins

gall bladder: stores and releases bile into the small intestine when needed to aid in the digestion of fats

small intestine: primary site of nutrient absorption, also absorbs nutrients and water

large intestine: absorbs water and electrolytes from undigested food material and forms feces

Rectum: stores feces until they can be eliminated through the anus during a bowel movement

stomach acid secretion, enzyme secretion, instestinal surface area

peristalsis: rhythmic contractions of the smooth muscle in the walls of the digestive tract, help move food along

Spinchter: ring of muscle that surrounds an opening or passage in the body that controls its opening and closing

gastrin is released by cells to help break down food, secretin released by small intestine in response to partially digested food, insulin released by pancreas in response to presence of glucose in blood