1. Animal Kingdom: Comparative Anatomy
Lecture 20: Anatomy
Animal Kingdom: Comparative Anatomy
A.Collins
JSHS
Pre-AP Biology

2. What do animals do to survive?
Section 26-1
All
Animals
have
are
carry out
Eukaryotic cells
Heterotrophs
Essential functions
with
such as
No cell walls
Feeding
Respiration
Circulation
Excretion
Response
Movement
Reproduction

3. Invertebrate feeding and digestion
Invertebrates can either have intracellular or extracellular digestion:
Intracellular meaning that food is digested within each individual cell of the organism.
Examples: Sponges
Extracellular means that digestion occurs inside a digestive tract or cavity, then absorbed into the body.
Examples: mollusks, worms, arthropods, echinoderms

4. Invertebrate Digestive Systems
Section 29-2
Intestine
Gizzard
Crop
Mouth/anus
Pharynx
Mouth
Gastrovascular cavity
Annelid
Anus
Gastrovascular cavity
Cnidarian
Arthropod
Crop
Pharynx
Anus
Pharynx
Mouth
Mouth/anus
Stomach and digestive glands
Rectum
Flatworm
Intestine

5. Vertebrate Digestive Systems
The digestive systems of many vertebrates have organs that are well adapted for different feeding habits.
Carnivores, such as sharks have short digestive tracts that produce fast-acting digestive enzymes.
Herbivores have long intestines that have large colonies of bacteria that help in digesting the cellulose fibers in plant tissues.

6. The Digestive Systems of Vertebrates
Section 33-3
The Digestive Systems of Vertebrates
Shark
Salamander
Lizard
Pigeon
Cow
Esophagus
Stomach
Intestine
Liver
Gallbladder
Pancreas
Cloaca
Crop
Gizzard
Cecum
Rectum

7. Aquatic invertebrates
Respiration in animals
Aquatic invertebrates
Aquatic animals have natural moist respiratory surfaces, and some respire through diffusion through their skin and others use gills.
Terrestrial Invertebrates
There are many different respiratory specialized organs in terrestrial invertebrates.
Spiders use parallel book lungs
Insects use openings called spiracles where air enters the body and passes through a network of tracheal tubes for gas exchange
Snails have a mantel cavity that is lined with moist tissue and an extensive surface area of blood vessels.

8. Invertebrate Respiratory Systems
Section 29-2
Invertebrate Respiratory Systems
Tracheal tubes
Gill
Siphons
Movement of water
Spiracles
Insect
Mollusk
Airflow
Spider
Book lung

9. Vertebrate respiratory systems
Chordates have one of two basic structures for respiration:
Gills – for aquatic chordates
Example: tunicates, fish and amphibians
Lungs - for terrestrial chordates
Examples: adult amphibians, reptiles, birds, and mammals

10. Aquatic Gills Vertebrate Lungs
Water flows through the mouth then over the gills where oxygen is removed
Carbon dioxide and water are then pumped out through the operculum
Section 33-3
Vertebrate Lungs
Nostrils, mouth, and throat
Trachea
Lung
Air sac
Salamander
Lizard
Primate
Pigeon

11. Open circulatory systems
Invertebrate Circulatory systems
Invertebrate circulatory system can range from a system where cells simply do diffusion to take in oxygen or systems with many hearts and even systems with one heart.
Open circulatory systems
Blood is pumped through a system of vessels BUT is only partially contained in these vessels. Most of the time the blood is pumped through open cavities.
This system is beneficial to arthropods and mollusks because the blood comes into direct contact organs and tissues.
Closed circulatory systems
A closed system forces blood through vessels that extend throughout the body of the organism. Since the system is “closed” the blood never leaves the vessels.
This system is beneficial to larger organisms because the blood is kept at a higher pressure which allows for more efficient circulation within the organism.

12. Invertebrate Circulatory Systems
Section 29-2
Invertebrate Circulatory Systems
Heartlike structure
Hearts
Small vessels in tissues
Heart
Blood vessels
Sinuses and organs
Blood vessels
Heartlike structures
Insect: Open Circulatory System
Annelid: Closed Circulatory System

13. Vertebrate circulatory systems
Chordate circulatory systems range from a single loop system (found in organisms with gills) to double loop systems.
Double-Loop Circulatory System
Single-Loop Circulatory System
FISHES
CROCODILIANS, BIRDS, AND MAMMALS
MOST REPTILES

14. Aquatic Invertebrate excretion
Some aquatic invertebrates simply diffuse ammonia out their bodies into the surrounding water where it is diluted and carried away.
Example: sponges, cnidarians, and some round worms.
Other aquatic invertebrates swell up with water, dilute the wastes and excrete the wastes through tiny pores in their skin.
Terrestrial Invertebrate excretion
Many terrestrial invertebrates convert ammonia into urea.
Urea is a simpler nitrogenous compound that is much less toxic than ammonia.
This urea is eliminated from the body in urine

15. Invertebrate Excretory Systems
Section 29-2
Invertebrate Excretory Systems
Flame cells
Flatworm
Excretory tubules
Nephrostome
Excretory pore
Flame cell
Excretory tubule
Nephridia
Digestive tract
Annelid
Malpighian tubules
Arthropod

16. Vertebrate Excretion
Aquatic vertebrates kidneys and rely on gill slits to release excretory wastes into surrounding water for dilution.
Terrestrial vertebrates rely on the kidney’s to filter out the ammonia and change it into urea and send it to be released in urine.

17. Nervous system
All animals respond to their environment through specialized cells called nerve cells.
In most animals nerve cells hook together to form the nervous system.
Nervous systems can range from fairly simple to extremely complex.
The arrangement of nerve cells from phylum to phylum can be dramatically different.

18. Invertebrate Nervous Systems
Section 29-2
Invertebrate Nervous Systems
Vertebrate Nervous Systems
Arthropod
Brain
Ganglia
Ganglia
Brain
Flatworm
Mollusk