Deuterostomes and Chordata Lecture Notes

Flashcards about Deuterostomes, Echinodermata, Chordata and Vertebrata

What are the key features of deuterostomes?

Blastopore becomes the anus, radial indeterminate cleavage, coelom development, triploblastic and coelomate, bilateral symmetry, internal skeleton.

How is the Sea Lamprey being used in research at Stowers?

Lamprey can regenerate their spinal cord so this can be a way to study that process. They are also used to study the immune system and gene regulation of development.

How is the Sea Squirt being used in research at Stowers?

Transparent during development, which makes them a good model to look at gene expression and cell diVerentiation during development.

How are Mice being used in research at Stowers?

They have many similarities to humans , so can be used to study a variety of medical diseases (cancer, osteoporosis, high blood pressure and diabetes mellitus).

What are the key distinguishing features of Phylum Echinodermata?

Coelomates, Radial Symmetry (in adults), Endoskeleton of Calcareous Plates, Water Vascular System, No Head or Brain, Regeneration, Marine Habitat, No Excretory Organs

What is the function of the water vascular system in echinoderms?

Functions primarily in locomotion, feeding, respiration, and sensory perception.

What is the sieve-like opening on the body surface that allows seawater to enter in echinoderms?

Madreporite

What is the water vascular system of echinoderms?

The water vascular system is a network of fluid- filled canals derived from the coelom, operating hydraulically to control the movement of tube feet.

What is the significance of radial symmetry for adult echinoderms?

The radial symmetry in adults allows them to interact with their environment equally from all sides, which is useful for activities like feeding and defense on the ocean floor.

What are the key characteristics of Echinoderm Endoskeletons?

Internal (beneath the skin), Calcium carbonate ossicles, Grows with the organism, May be flexible or rigid, Support, protection, and movement, Covered by a thin epidermis

What are the key characteristics of Arthropod Exoskeletons?

External (covers the body surface), Chitin (sometimes hardened with proteins/minerals), Does not grow; must be shed, Generally rigid, Protection, support, and muscle attachment, Exposed or covered with waxy layer

What are the four chordate features?

Notochord, Dorsal Hollow Nerve Cord, Pharyngeal Slits (or Pouches), Post-Anal Tail

What is the function of the Notochord?

Provides support and defines the primitive axis of the embryo. In vertebrates, it is usually replaced by the vertebral column during development.

What does the Dorsal Hollow Nerve Cord develop into?

Develops into the central nervous system—the brain and spinal cord—in most chordates.

What are the key features of the Subphylum Urochordata?

Larvae have all chordate traits, Adults lose notochord, tail, and nerve cord, Sessile, filter-feeders, Covered by a tunic.

What are the key features of the Subphylum Cephalochordata?

Retains all chordate traits for life, Notochord runs full body length, No backbone, Simple structure, marine.

What are the key features of the Subphylum Vertebrata?

Notochord replaced by vertebral column, Skull protects brain, Advanced organ systems, Complex and diverse group.

What are key characteristics of fishes?

Aquatic Vertebrates, Streamlined Body, Fins for Movement, Scales, Gills for Respiration, Cold-blooded (Ectothermic), Two-chambered Heart, Lateral Line System, Reproduction, Swim Bladder (in bony fishes)

What distinguishes fish in Class Chondrichthyes from fish in Classes Actinopterygii, Dipnoi and Actinistia?

Skeletons are made of cartilage, They lack a swim bladder, Exposed gill slits without an operculum, and they typically reproduce through internal fertilization.

What are key characteristics of Class Amphibia?

Dual Life Cycle, Moist, Permeable Skin, Three-Chambered Heart, Ectothermic, Reproduction in Water, Legs for Movement on Land

What adaptations were needed for amphibians to inhabit land?

Lungs, moist, permeable skin, stronger skeletons and muscular limbs, eyelids and tear glands, tympanic membranes (eardrums)

List several diVerent animals that are amphibians.

Frogs, Toads, Salamanders, Newts

What are key characteristics of Class Reptilia?

Scaly Skin, Ectothermic (Cold-blooded), Internal Fertilization, Amniotic Egg, Three-Chambered Heart, Lungs for Respiration, Efficient Excretory System, Well-Developed Limbs, Keen Senses

List several different animals that are reptiles.

Snakes, Turtles, Tortoises, Lizards, Crocodiles, Alligators

What is the Amnion and what is its function?

Forms a fluid-filled sac around the embryo called the amniotic sac which cushions and protects the embryo from shock and drying out.

What is the Chorion and what is its function?

Outermost membrane that surrounds all other membranes which is involved in gas exchange between the embryo and the outside environment.

What is the Allantois and what is its function?

Stores nitrogenous waste produced by the embryo and also aids in gas exchange as it fuses with the chorion in some species.

What is the Yolk Sac and what is its function?

Contains the yolk, which is the food source for the developing embryo and supplies nutrients throughout development.

What does it mean to be ectothermic?

An animal relies on external sources of heat—like the sun or warm surfaces—to regulate its body temperature.

What is the Carapace?

The dorsal (top) part of the shell, typically convex, and provides protection for the turtle's back, covering vital organs and defending the animal against predators and environmental elements.

What is the Plastron?

The ventral (bottom) part of the shell. It is usually flattened and shields the turtle's belly.

What is the Parietal Eye?

A specialized light-sensitive organ found in some reptiles, particularly in lizards and certain amphibians. It is located on the top of the head, and although it is not used for vision in the same way as the eyes, it plays an important role in detecting light and temperature changes.

What are key characteristics of Class Aves?

Feathers, Hollow Bones, Endothermic (Warm-Blooded), Beak (Bill), Four-Chambered Heart, Efficient Respiratory System, Wings and Flight Adaptations

What do Birds and Reptiles have in common?

They have internal fertilization and amniotic eggs.

What are three adaptations that allow birds to fly?

Lightweight, Hollow Bones, Feathers, Powerful Flight Muscles and Keeled Sternum

What are key characteristics of Class Mammalia?

Hair or Fur, Mammary Glands, Warm-Blooded (Endothermic), Vertebrates with a Backbone, Live Birth (with Few Exceptions), Specialized Teeth, Three Middle Ear Bones, Endothermic Circulatory System, Highly Developed Brain, Advanced Respiratory System

What features distinguish monotremes?

Egg-laying, Young hatch from eggs and are fed milk, No placenta, Cloaca, no nipples

What features distinguish marsupials?

Live birth of underdeveloped young, Young develop in a pouch or on the mother's body, Simple placenta, Pouch for development

What features distinguish placental mammals?

Live birth of fully developed young, Young are nourished via the placenta in the womb, Complex placenta, Nipple feeding, long gestation period