Chordates and Animal Systems Flashcards

Practice flashcards covering chordate biology, vertebrate characteristics, tissue and organ system functions, and animal physiology as well as reproduction and communication signals.

What phylum do chordates belong to?

Chordata

Which key subphyla make up the chordates?

Urochordata, Cephalochordata, and Vertebrata

Are Urochordata classified as vertebrates or invertebrates?

Invertebrates

What are two common examples of Urochordata?

Tunicates and sea squirts

When do Urochordates display more prominent chordate characteristics?

During the larval stage

Are Cephalochordata invertebrates?

Yes

What is a primary example of Cephalochordata?

Lancelets

What do Cephalochordates resemble in appearance?

Fish

Are members of Vertebrata classified as invertebrates or vertebrates?

Vertebrates

What are the four main characteristics shared by all chordates?

Notochord, dorsal hollow nerve cord, pharyngeal slits, and post-anal tail

What is the semi-rigid, elongated structure in chordates called?

The notochord

Where does the notochord run in the body?

From anterior to posterior

What is the physical structure of the notochord?

A fibrous sheath filled with fluid-filled cells

List three functions of the notochord.

Support, lateral bending, and muscle attachment

What is the dorsal hollow nerve cord?

A single, dorsal structure parallel to the digestive tract and notochord

What does the anterior part of the dorsal hollow nerve cord develop into?

The brain

What does the posterior portion of the dorsal hollow nerve cord become?

The spinal cord

Where are pharyngeal slits located?

In the throat region

What do pharyngeal slits resemble in fish?

Gills

What is the function of pharyngeal slits in protochordates?

To filter food

What is the function of pharyngeal slits in aquatic vertebrates?

They serve as gills

In tetrapods, what structures do pharyngeal slits develop into?

Ears, tonsils, and glands

What is a post-anal tail?

A tail that extends beyond the anus

What is the primary function of the post-anal tail?

Movement (swimming, climbing, etc.)

What is the basic difference between vertebrates and invertebrates?

Vertebrates have bones, whereas invertebrates lack them

What is the most diverse and largest group of vertebrates?

Fishes

How many classes of fishes are recognized?

5 classes

What does the term 'Agnatha' refer to?

Jawless fishes

What are two examples of Agnatha?

Myxini (hagfish) and Petromyzontida (lampreys)

What is Petromyzontida the scientific name for?

Lampreys

What is Myxini the scientific name for?

Hagfish

What does 'Gnathostomata' refer to?

Jawed fishes

What are Chondrichthyes?

Cartilaginous fishes like sharks and rays

What are Osteichthyes?

Bony fishes

What are the two specific groups within Osteichthyes?

Actinopterygii and Sarcopterygii

What is Actinopterygii?

Ray-finned bony fish

What is Sarcopterygii?

Lobe-finned bony fish

How many major characteristics of vertebrates are listed?

6 characteristics

What is an endoskeleton?

An internal skeleton or backbone

What does 'Craniata' mean?

Vertebrates possessing a skull and a complex nervous system

What specific organs are enclosed by the cranium?

Brain, eyes, ears, and olfactory organs

What is the role of neural crest cells?

They form teeth, bones, cartilage, and neurons

What is the function of Hox genes?

To specify the body plan and organization

How many sets of Hox genes do vertebrates usually have?

2 or more sets

What are segmented myomers?

Muscle segments found in fishes and amphibians

What key survival ability do most vertebrates possess?

The ability to live independently

Which vertebrates are an exception to the rule of independent living?

Ectoparasitic fishes

What is the amnion?

A membrane that encloses the embryo

What are anamniotes?

Animals that lack an amnion

What are two examples of anamniotes?

Fishes and amphibians

What are amniotes?

Animals that possess an amnion

What are three examples of amniote groups?

Reptiles, birds ($Aves$), and mammals

List the 6 traits of amniotes.

Amniotic egg, thick waterproof skin, expanded throat cavity, stronger jaws, high-pressure cardiovascular system, and expanded brain and sensory organs

What is an amniotic egg?

An egg with specialized membranes to support embryo development on land

What is the function of the chorion?

Gas exchange: it removes $CO_2$ and provides $O_2$

What is the function of the amnion in the egg?

It is a fluid-filled membrane that encloses the embryo

What is the function of the allantois?

It stores metabolic waste

On what basis are vertebrate skull patterns classified?

The number of temporal openings (holes) excluding eye holes

What is an anapsid skull?

A skull with 0 temporal holes

Give an example of an organism with an anapsid skull.

Turtles

What is a synapsid skull?

A skull with 1 temporal hole

Which animal group is characterized by a synapsid skull?

Mammals

What is a diapsid skull?

A skull with 2 temporal holes

What are examples of organisms with diapsid skulls?

Lizards, snakes, and birds

Which larger group are diapsids specifically associated with?

Archosaurs

Mammals are categorized as which type of animal?

Vertebrates

What are the 3 major groups of mammals?

Ornithodelphia, Eutheria, and Metatheria

What are monotremes?

Egg-laying mammals

What is the scientific name for the monotreme group?

Ornithodelphia

Do monotremes have a placenta or nipples?

No

What are eutherians?

Placental mammals

Where does development occur for eutherians?

Inside the womb

What type of placenta do eutherians possess?

A complex placenta

What are metatherians?

Marsupials

How do metatherian offspring develop?

They are born prematurely and continue development in a pouch

What type of placenta is found in metatherians?

A simple placenta

What are two examples of metatherians?

Kangaroos and koalas

In animal form and function, what is a tissue?

A group of similar cells that performs a specific function

What are the four main types of tissues in animals?

Epithelial, connective, muscle, and nervous

What is the function of epithelial tissue?

It protects the body and faces the external environment

What are the three core cell shapes of epithelial tissue?

Cuboidal, columnar, and squamous

What is simple epithelial tissue?

Tissue consisting of 1 layer of cells

What is stratified epithelial tissue?

Tissue consisting of multiple layers of cells

What is pseudostratified epithelial tissue?

A single layer of cells with varying lengths

What is the general role of connective tissue?

To support, bind, and connect structures throughout the body

Name the 6 main types of connective tissue.

Loose, fibrous, bone, cartilage, adipose, and blood

What is the specific function of loose connective tissue?

It binds and holds tissues in place

What is the function of fibrous connective tissue?

It connects tendons and ligaments to bones

What is the role of bone tissue?

Support

What is the role of cartilage tissue?

Support

What is the function of adipose tissue?

It stores metabolic energy

What are the three main functions of blood as a connective tissue?

Oxygen transport, immune defense, and blood clotting

What is the primary role of muscle tissue?

To help with movement

How does muscle tissue function mechanically?

Long muscle fibers contract when they receive nerve signals

What is the function of nervous tissue?

To receive, process, and transmit information

What are the two types of cells found in nervous tissue?

Neurons and glia

What do neurons do?

They transmit signals

What is the function of glia?

They hold neurons in place and assist with signal transmission

What three core elements do tissues need to survive?

Oxygen, water, and nutrients

How do animals generally obtain oxygen?

Through gills or lungs