Chapter 29: Chordates

Chordates share five characteristics that are always present in the embryonic/juvenile stage, including a dorsal hollow nerve cord, which is defined as a ___

hollow tube located on the back end, direct from ectoderm that often gets filled by the spinal cord in some chordates

Chordates share five characteristics that are always present in the embryonic/juvenile stage, including a post anal tail, which is defined as a ___

structure located posterior to the anus

Chordates share five characteristics that are always present in the embryonic/juvenile stage, including pharyngeal slits, which are defined as a ___

opening of the pharynx extending to the outside environment that often turns into gills for fish

Chordates share five characteristics that are always present in the embryonic/juvenile stage, including a notochord, which is defined as a ___

flexible rod-shaped structure located between the digestive tube and nerve cord that often develops into the vertebral column

Chordates share five characteristics that are always present in the embryonic/juvenile stage, including an endostyle/thyroid gland, which is defined as a ___

structure located in the neck that secrete hormones, and regulates calcium metabolism in humans

Cephalochordates (Lancelets) are defined as ___

aquatic invertebrate chordates whose notochord extends into the head, lacks a well-defined brain, has a simple nervous system, and resides in sand at the sea floor

Urochordates (Tunicates) are defined as ___

aquatic invertebrate chordates whose body is covered in tunic (cellulose-like material), and lacks a notochord, nerve cord, and post-anal tail

all vertebrates have a cranium (head), which is defined as a ___

bony, cartilaginous, or fibrous structure surrounding the brain, jaw, (not always necessary), and facial bones

myxini (hagfish) are defined as

a group of marine craniates with a partial cranium made of cartilage, but no vertebrae

all vertebrates have a vertebral column, which is defined as a ___

dorsal supporting structure that replaces the notochord during early development and allows organisms to grow more

Petromyzontida (lampreys) are defined as ___

the most primitive vertebrates who lack a jaw, have a rasping tongue with a toothed, funnel-like sucking mouth, a notochord, and are often parasites to fish

all vertebrates have a well developed ___ system on the heart side of the body, and a rigid ___ system, not always bone

circulatory, skeletal

a true jaw is defined as ___

a hinge structure attached to the cranium that moves, allowing for attacking and tearing

Gnathostomes are defined as

vertebrates that have a jaw, mouth, and at least 2 sets of fins—all of which help organisms hunt and move with more control (e.g., jawed fishes)

Gnathostomes have pectoral fins, which are located ___

on the anterior body

Gnathostomes have pelvic fins, which are located ___

on the posterior

Cartilaginous Fishes (Chondrichthyes) are defined as ___

fish with a skeleton (jaw, vertebral column, cranium) composed of firm, pliable cartilage (e.g., sharks, rays, sawfishes)

sharks reproduce sexually via ovoviviparous, during which fertilization is ___

internal, eggs hatch in the uterus, and young are born alive and fully functional

Bony Fishes (osteichthye) are defined as ___

fish with an internal skeleton (jaw, vertebral, column, cranium) of calcified rigid bone, overlapping scales with an inner layer (connective tissue) and outer layer (calcium), and membrane covered gills

Bony Fishes (osteichthye) have an operculum, which is defined as ___

gills protected by plates

Bony Fishes (osteichthye) have dorsal fins (at least one), which are located on the ___

dorsal side for more stability

Bony Fishes (osteichthye) have caudal fins, which are located on the ___

caudal/posterior side for additional support

Bony Fishes (osteichthye) have a swim bladder, which is defined as a ___

gas-filled organ that helps with buoyancy control

Lobe finned fish are a type of Bony Fishes (osteichthye) that have the presence of ___

thick, supportive bones in the fins that allow them to walk around the surface

Ray finned fish are a type of Bony Fishes (osteichthye) that have the presence of ___

thin, smaller fins

Tetrapods are defined as

vertebrates suspected to have evolved from aquatic lobe-limbed bony fish who became adapted to life on land for terrestrial food sources, eventually gaining 4 limbs

Amphibians are defined as___

tetrapods with a “dual life” because of the metamorphosis many undergo, and the mixture of aquatic and terrestrial environments throughout life

Frogs (Anura) are defined as ___

amphibians whose reproduction, fertilization, development, and metamorphosis/limb development occurs in the water

Salamanders (Urodela) are defined as ___

amphibians who require regular water access, lack lungs but respirate through the skin (exceptions) and move side to side

Caecilians (Apoda) are defined as ___

amphibians whose limbs are present in juvenile stages but lost in adulthood, are nearly blind, and bury beneath the soil

Amniotes are defined as ___

tetrapods who lay terrestrially adapted eggs protected by amniotic membranes providing the embryo with an aquatic environment, allowing the amniotes to reside in drier environments

Reptiles are defined as ___

amniotes who lay eggs enclosed in shells on land, reproduce sexually via internal fertilization, have scaly skin made of keratin and waxy lipids for reduced water loss, have lungs, and are ectothermic (body temperature depends on external environment)

Squamates are reptiles that are defined as ___

lizards, who vary in size, are carnivores, but some (e.g., iguanas) are herbivores; and snakes, who are carnivores, and many have a flexible skull with 8 rotational joints

Testudines (turtles) are defined as ___

reptiles who have a bony or cartilaginous shell with a ventral surface (plastron) and a dorsal surface (carapace) developing from the ribs

Pterosaurs are reptiles defined as ___

pseudodinosaurs who developed the ability to fly, and whose wings are membrane-surrounded arms

Ornithischians and Sauropods are reptiles defined as ___

true dinosaurs who were herbivores

Theropods are reptiles defined as ___

bird ancestors who evolved from bipedal dinosaur predators that have similar hip and wrist bone structures

birds are the only endodermic reptiles, which mean that they have the ability to ___

regulate their internal temperature

bird’s feathers provide insulation and allow for flight. secondary feathers are ___ and provide ___, whereas primary feathers are ___ and provide ___

medial, lift, lateral, thrust

Mammals share four characteristics, including sweat glands, which ___

secrete evaporated sweat

Mammals share four characteristics, including mammary glands, which ___

secrete milk for newborns (in females)

Mammals share four characteristics, including hair, which ___

provides protection and insulation

Mammals share four characteristics, including a four ___

chambered heart

Monotremes are defined as ___

the smallest, most primitive mammals who lay eggs rather than give birth

Marsupials are defined as ___

mammals who possess a pouch (mammary glands located) where premature young reside after birth, receive milk, and continue growing

Eutherians (placental mammals) are defined as ___

the most widespread mammals who possess a complex placenta connecting the fetus and mother and allowing for gas, fluid, and nutrient exchange

Primates evolved from relatively small ___

arborea, insectivorous eutherians

Prosimians are a type of primates consisting of ___

lemurs, and lorises and galagos

Antrhopoids are primates that include ___

monkeys, apes, and humans

Lesser Apes are Antrhopoids that include ___

gibbons

Great Apes (Family Hominidae) are Antrhopoids that include genera ___

Pan (chimpanzees and bonobos), Gorilla (gorillas), Pongo (Orangutanes), and Homo (humans)