Compare and Contrast the Frog and Perch

What is an Animal?

Chapter 25.1

Characteristics of Animals• All animals share six characteristics…–All animals are members of the kingdom Animalia–All animals are heterotrophic –All animals are multicellular–All animals are eukaryotic organisms –All animal cells lack a cell wall–All animals have the ability to move• Animals ability to move from place to place helps

them find food, move to favorable environments, and avoid predators • There are many different forms of movement (swim

walk, fly, and running)• Some animals move by attaching themselves to the

ocean floor or submerged surfaces

Invertebrates vs. ChordatesInvertebrates

• Includes 95% of all animal species

• Includes all animals that lack a backbones, or vertebral column

• Does not form a clade or any other true category in the classification system. (because it talks about characteristics animals lack)

• Examples: sea stars, jellyfish, worms, insects

Chordates• Includes fewer than 5% of

all animal species• All chordates share four

common characteristics during at least one stage of their lives– 1. ) have a dorsal, hollow

nerve cord– 2.) have a notochord– 3.) have a tail that extends

beyond the anus– 4.) have pharyngeal pouches

Notochord- is a long supporting rod that runs through the body just below the nerve cord

Pharyngeal Pouches- are paired structures in the throat region, also called the pharynx.

In fish pharyngeal pouches may turn into gills.

Invertebrates vs. ChordatesInvertebrates Chordates

• Non-vertebrate chordates are chordates that lack vertebrae

• Chordates with backbones are called Vertebrates– All Vertebrates have a

cranium and internal skeleton

– Examples: fishes, amphibians, reptiles, birds, and mammals

What Animals Do to Survive

• All animals must perform similar functions to stay alive.–1.) Maintain homeostasis by gathering and

responding to information–2.) Obtain and distribute oxygen and

nutrients–3.) Collect and eliminate carbon dioxide and

other wastes –4.) Reproduce

Maintaining Homeostasis• Homeostasis is maintained by feedback

inhibition.• Feedback inhibition (negative feedback)- is a

system in which the product or result of the process limits the process itself.

• Ex. If your house gets to cold, then your thermostat turns on the heat. As heat warms the house the thermostat turns the heater off

Gathering and Responding to Information

• Complex animals use several linked body systems to respond to an event

• The nervous system helps respond to events by using cells called receptors – Receptors respond to light, chemicals, sound and other

stimuli – Other nerve cells process the information and

determine how to respond – Animals often respond by moving around – Muscle tissues generate force by becoming shorter

when stimulated by the nervous system– Muscles work together with the skeleton to make up

the musculoskeletal system

Gathering and Responding to Information

• Skeletons vary widely from phylum to phylum– Invertebrates have skeletons that are flexible and

function through the use of fluid pressure– Can have either Internal or external skeletons• Internal skeletons are made from the bones of the

vertebrae (found inside the body)• External skeletons are found outside the body

• • External Skeleton Internal Skeleton

Obtaining and Distributing Oxygen and Nutrients

• All animals must breathe to obtain oxygen– Small animals obtain oxygen by allowing it to diffuse

across their skin– Larger animals use gills, lungs, or air passages

• All animals must eat to obtain nutrients• Nutrients and oxygen are distributed to cells

throughout the body using a circulatory system• The structures of the respiratory and digestive

system work together with the circulatory system

Collecting and Eliminating CO2 and Other Wastes

• Animals’ metabolic processes create carbon dioxide and other waste products that contain nitrogen often in the form of ammonia

• Carbon dioxide and ammonia are toxic and must be excreted and eliminated from the body

• Many animals remove CO2 with their respiratory system. More complex animals have a specialized organs system for eliminating waste called the excretory system

• Before wastes can be eliminated they need to be collected from cells throughout body tissues and then delivered to the excretory or respiratory system

Reproducing• Most animals reproduce sexually by producing

haploid gametes.• Sexual reproduction creates and maintains genetic

diversity.– Genetic diversity increases a species’ ability to evolve

and adapt as the environment changes• Invertebrates and a few vertebrates reproduce

asexually– Asexual reproduction produces offspring that are

identical to the parent– Asexual reproduction allows animals to increase their

numbers rapidly , but does not generate genetic diversity

25.1 Vocabulary• Invertebrates- includes all animals that lack a back

bone or vertebral column • Chordates- animals that have had a dorsal, hollow

nerve cord, a notochord, a tail that extends beyond the anus, and pharyngeal pouches during at least one stage of their life

• Notochord- is a long supporting rod that runs through the body just below the nerve cord

• Pharyngeal Pouches- are paired structures in the throat region, also called the pharynx.

• Vertebrates- chordates with backbones• Feedback Inhibition- also known as negative feedback,

is a system in which the product or result of the process limits the process itself

• Using a new Venn Diagram compare and contrast Chordates and Invertebrates…