Unit 4 Flashcards

Flashcards covering key vocabulary and concepts from Chapters 32, 33, and 34 of the lecture notes.

Collagen

A structural protein that is a major component of connective tissues in animals.

Bilateral Symmetry

Body plan in which the left and right sides are mirror images of each other.

Diploblastic

Refers to animals having two embryonic cell layers: ectoderm and endoderm.

Hox Genes

Regulatory genes that dictate the body plan and segment identity during development.

Protostome

A clade of animals where the blastopore becomes the mouth during embryonic development.

Echinoderms

Marine animals characterized by their radial symmetry, endoskeleton, and water vascular system.

Lamenellar tissue

A type of specialized tissue in animals that provides support and structure.

Metamorphosis

A developmental process in which an organism undergoes a significant transformation.

Cephalopoda

A class of mollusks including squids and octopuses that have a well-developed head and complex eyes.

Amniotic Egg

An egg that has a protective shell and several membranes to support the embryo.

Viviparous

Referring to animals that give birth to live young instead of laying eggs.

Tardigrada

Microscopic, water-dwelling animals known for their resilience in extreme environments.

Chordates

Animals possessing a notochord at some stage of their life cycle.

Cartilaginous Fishes (Chondrichthyes)

A class of fishes characterized by a skeleton made of cartilage rather than bone.

Ectothermic

Organisms that rely on external sources to regulate their body temperature.

Synapsid skull

A type of skull with a single temporal fenestra, characteristic of mammals and their ancestors.

Cambrian Explosion

A sudden increase in the diversity of animal life during the Cambrian period.

Radula

A toothed, chitinous ribbon used by mollusks to scrape food.

Cnidocytes

Specialized cells in cnidarians that contain stinging structures called nematocysts.

Endothermic

Organisms that can regulate their body temperature internally, often referred to as warm-blooded.

Myriapods

A group of arthropods that includes centipedes and millipedes.

Metamerism

The segmentation of the body into repeating units, as seen in annelids.

Connective Tissues

Tissues that support, connect, or separate different types of tissues and organs in the body.

Ectoderm

The outermost germ layer of an embryo, which gives rise to the epidermis and nervous system.

Endoderm

The innermost germ layer of an embryo, which gives rise to the lining of the digestive tract and associated organs.

Blastopore

The opening of the archenteron in the gastrula that develops into the mouth in protostomes and the anus in deuterostomes.

Radial Symmetry

Body plan in which body parts are arranged concentrically around a central axis.

Endoskeleton

An internal skeleton, such as the bony or cartilaginous skeleton of vertebrates.

Water Vascular System

A network of fluid-filled canals in echinoderms used for locomotion, feeding, and gas exchange.

Mollusks

A diverse phylum of invertebrates including snails, clams, and octopuses, typically characterized by a soft body and a mantle.

Arthropods

An invertebrate animal of the large phylum Arthropoda, such as an insect, spider, or crustacean, characterized by an exoskeleton, segmented body, and paired jointed appendages.

Cnidarians

A phylum of aquatic invertebrate animals, including jellyfish, corals, and sea anemones, characterized by stinging cells (cnidocytes).

Nematocysts

Barbed, thread-like stinging structures found within cnidocytes, used for defense and prey capture.

Notochord

A flexible, rod-like structure that forms the main support of the body in the embryonic stage of all chordates and in the adult of some.

Cartilage

A flexible connective tissue found in many parts of the body, including joints, nose, and ears.

Temporal Fenestra

An opening in the temporal region of the skull, found in many amniotes, that provides space for jaw muscles.

Annelids

A phylum of segmented worms, including earthworms and leeches, characterized by metamerism.