1. A Brief Survey of Animals
Animalia

2. The study of animals is referred to as zoology.
Animals are the largest of the 6 kingdoms, and exhibit a great diversity in form and function.

3. Major Animal Characteristics
1. Multicellular, eukaryotic organisms, with a division of labour amongst cells that are specialized.
2. A variety of systems have evolved and are specialized for specific functions. These systems include:
- Circulatory
- Integumentary (skin)
- Lymphatic
- Digestive
- Skeletal
- Respiratory
- Excretory
- Muscular
- Endocrine
- Reproductive
- Nervous

4. 3. Heterotrophic: Animals have more complex systems than plants
3. Heterotrophic: Animals have more complex systems than plants. These systems are based upon the animal’s nutrient requirements.
4. Locomotion: Most are mobile at some point in their lifetime.
5. Reproduction: This may be through sexual or asexual means. Asexual occurs in some lower forms, sexual occurs in all higher forms.

5. Five Major Areas Used to Describe Animals
1. Systems: When moving from simpler to more complex animal forms, the number and complexity of systems increases.
In the case of digestion, all animals except Poriferans digest food extracellularly, meaning outside of their cells. Poriferans digest food intracellularly, within their cells. Animal digestive systems can be either :
Incomplete: two way system. Having only one opening to the gut. Both food and waste enter and exit the same opening.
Complete: one way system, having two openings to the gut. Food enters one way, exits the other.

6. Intracellular digestion
Extracellular digestion

7. 2. Symmetry: This is a term used to describe the body plan of an animal. To find the symmetry of an animal, an imaginary line is drawn to divide the animal in half.
There are three forms of symmetry:

8. (A) Asymmetric - An organism cannot be cut into two matching halves. (e.g. sponges)
(B) Radial - Any line passing through the central axis of an organism divides it in half. These organisms are rounded. (e.g jellyfish)
(C) Bilateral: An elongated body plan. There is only one line that divides the animal in half. This line runs down the middle of the longitudinal section. This is the most common form of symmetry. (e.g. humans, frogs, etc.)

9. Body Symmetry

10. Posterior: rear region Dorsal: back region Ventral: bottom region
When an animal has bilateral symmetry, the body can be divided into 5 regions:
Anterior: head region
Posterior: rear region
Dorsal: back region
Ventral: bottom region
Lateral: side region
The body symmetry of all animals is related to the necessity of them to move in order to obtain food. This is why most sensory organs are located at the anterior end of the animal.

11. 3. Coelom
A coelom is a body cavity. The presence or absence of a fluid-filled cavity is one of the most significant features of animal body plans used in classification.
The coelom is located between the digestive tract and the body wall.
The peritoneum is associated with organisms which have a true coelom. The peritonem lines body cavities and covers internal organs. It may provide support and hold internal organs in place.

12. Body cavities are important for the following reasons:
(i) They provide space in which internal organs can be suspended so they are not negatively affected by muscle pressure and body movement.
(ii) They provide space for internal organs to develop and expand.
(iii) They contain fluids which may assist in internal transportation and nutrient and gas exchange.
Lower animal forms have no or partial coeloms. They are at a disadvantage in light of the efficient functioning of a true coelom.

13. Development of coelum

14. Ectoderm - forms the outer body (skin, nerves)
4. Cell Layers: Animals contain either two or three embryonic cell layers. Simpler animals contain only two; all others have three. Each layer is responsible for producing various tissues and structures in the adult animal. These layers include:
Ectoderm - forms the outer body (skin, nerves)
Mesoderm - forms the middle organs (kidney, heart, urinary, skeletal and muscular)
Endoderm - form lining of gut or digestive tract, lungs,liver,pancreas
simple animals have no mesoderm.

15. Germ layers

16. 5. Reproduction: Moving from simpler to more complex animal forms, the reproductive system becomes more complex.
Animals have the ability to reproduce sexually and asexually. Several invertebrates classes have the ability to reproduce asexually, whereas all vertebrates reproduce sexually.

17. Reproduction

18. Classification
There are two major groups of animals. They are classified according to the presence or absence of a backbone.
Invertebrates
lacking a backbone
Roughly 97% of the animal kingdom
Vertebrates
Having backbone
Roughly 3% of the animal kingdom

19. Invertebrates
1. These organisms lack a backbone, and include the following phyla:
(a) Porifera (sponge)
(b) Coelenterata (jellyfish)
(c) Platyhelminthes (tapeworm)
(d) Nematoda (ringworm)
(e) Annelida (earthworm)
(f) Mollusca (shellfish)
(g) Arthropoda (insects)
(h) Echinodermata (starfish)

20. 2. Make up 97% of the animal kingdom.
3. Higher forms are characterized by cephalization. This is an evolutionary tendency towards specialization of the body with concentration of sensory and neural organs in the anterior end( such as the brain).
4. They possess body plans which have been enormously successful both ecologically and evolutionarily.

21. Key Terms / Definitions Used in Animal Classification
Pseudocoelom - partial, not a true body cavity
2-way Digestive System - only one opening through which food enters and undigested food exits
1-way Digestive System - two openings. Food enters through the mouth and undigested food exits the anus.
One way system is better because it allows the animal to eat continuously.
Diffusion - a substance goes from an area of high to low concentration without any expenditure of energy
Open Circulatory System - blood is not always inside blood vessels, and is not under pressure. It is slow and inefficient, and does not transport oxygen.

22. Key Terms / Definitions (continued)
Closed Circulatory System - blood is always inside blood vessels, and is under pressure. It is fast, efficient and transports oxygen.
Ganglia - a mass of nerve cells that give rise to a nerve center.
Eye Spot - sensory organ capable of detecting light from dark, does not see images
Flame Cell - cells that contain cilia that push waste from an organism.
Nephridia - a unit that filters body fluids to remove waste so that the fluid may be recycled.

23. Key Terms / Definitions (continued)
Malpighian Tubules - tubules that collect liquid wastes within an organism and dump them into the hind gut of the organism
Green Glands - structures in which wastes are collected and become concentrated within an organism
Tracheals - tubes leading into the body of the organism for the purpose of gas exchange
Hermaphroditic - possessing both ovaries and testes

24. Phylum Porifera Means pore bearing Includes sponges
Are asymmetrical aquatic organisms made of two layers
They have one body opening that allows for food to enter and waste to pass, however they do not have a digestive system. All of their food is digested intracellularly.
Poriferans can reproduce asexually or sexually
Asexual via budding
Sexual via hermaphrodites( fertilization occurs external)
They do not possess any sensory organs nor do they possess a nervous system

25. Phylum Cnidaria Means thistle, referring to stinging tentacles
Includes Hydras, Sea Anemones, Jellyfish, and Coral
They are radially symmetrical, aquatic organisms made of two layers
They have one body opening through which food enters and waste leaves and unlike Poriferans, they have no digestive system, thus making it incomplete.
food is digested extracellularly
They reproduce asexually (budding) and sexually where organisms will either have opposite sexes or will be hermaphrodites
fertlization is external
Their circulatory, excretory, and respiratory system occur via diffusion
they have simple nervous system known as a nerve net

26. Phylum Platyhelminthes
Means flat wide worm therefore refers to flatworms
Includes Planarians, Flukes and Tapeworms
They are bilaterally symmetrical organism made of 3 germ layers that can be eitehr aquatic terrestrial or parasitic(living inside and feeding off other organisms)
They have only one body opening through which food enters and waste leaves. They do not have a digestive system thus because there is only one opening, the digestive system is known as incomplete
food is digested extracellularly
They reproduce asexually through regeneration or sexually with species having opposite sexes or in some cases species can be hermaphroditic
fertilization is internal

27. Their nervous system is simple , comprising of a primitive brain and nerve cords. Sensory organs are also very limited, with some species having eye spots- a sensory organ capable of detecting light from dark.
Their circulatory and respiratory systems occur via diffusion while their excretory systems are accomplished via flame cells
Flame cells are ciliated excretory cells found in lower invertebrates that function like a kidney to remove waste

28. Phylum Nematoda Means thread like commonly called roundworms
Includes pinworms and hookworms
They are bilaterally symmetrical organisms, made of 3 germ layers, that can be either aquatic, terrestrial or parasitic
They have 2 body openings, therefore have complete one way digestive system
food is digested extracellularly
They reproduce sexually with species having either opposite sex or in some cases species can be hermaphroditic
fertilization is internal
Like plathyelminthes, their nervous system are simple, made of a primitive brain and nerve cords. Their sensory capabilities are limited to touch.
Their circulatory and respiratory systems occur via diffusion and their excretory system is controlled by flame cells

29. Phylum Annelida
Means ring referring to body being segmented into repeating units
Includes earthworms, leeches and tubeworms
Bilateral symmetry, made of 3 germ layers, and are aquatic or terrestrial
Have 2 body openings, one way digestive n system and tube-tube body plan
food is digested extracellularly
Reproduce sexually with species of either opposite sex or hermaphrodites
fertilization is internal
Fairly simple nervous system made of primitive brain , some nerves and ganglia- a mass of nerve cell that give rise to a nerve center

30. The added neural attachments heightens their sensory capabilities, species are able to touch taset and sense light and moisture
Annelids have a closed circulatory system, ,meaning that at all times their blood is contained within vessels
Respiratory system occurs via diffusion through the skin
Their excretory system are controlled by organs called Nephridia
similar to flame cells nephrida function like kidneys, to remove wastes out of body. They filter body fluids , the pass wastes through to the organisms exterior.

31. Phylum Mollusca Means “soft bodied”
Includes Clam, Oysters, octopus, and snails
They are bilaterally symmetrical organism, made of 3 germ layers, that are mainly aquatic, but few do live on land- ie. Snails
They have two body openings, a one way complete digestive system and a tube within a tube body plan
Food is digested extracellularly
They reproduce sexually with species being of either opposite sexes or hermaphrodites
fertilization is primarily internal however some species do display external fertilization
Like annelids their nervous system is slightly more developed than previous phyla. They have primitive brain, a few nerves with ganglia. And like Annelids because of this their sensory abilities are heightened. They can sense touch taste smell and in some species vision is possible (octopus).

32. Have an open circulatory system, their blood is contained within vessels and therefore has the ability to slosh around
Many of they are aquatic and therefore they’ve adapted gills for respiration while those few species that live on land do have a very simple lung
Excretory system mainly controlled by nephridia

33. Phylum Arthropoda
Means jointed foot, arthropods have jointed appendages and hard exoskeleton
Includes insects, crustaceans, and centipedes
They are bilaterally symmetrical organisms , made of 3 germ layers that re aquatic, terrestrial and air borne
They have two body openings and one way complete digestive system
Food is digested extracellualrly
They reproduce sexually with species being either of opposite sexes or some being hermaphrodites
Fertilization is internal

34. They have open circulatory systems
Their nervous system are advanced compared to other invertebrates with that in mind their sensory abilities are also advanced. Many have the ability to hear taste smell touch and see
They have open circulatory systems
Have respiratory systems made of gills and tracheals. Tracheals are tubule networks involved in gas exchange
Excretory system made of malpighian tubules and green glands
Malpighian tubules: are a tubule network that collects liquid wastes and sends them to the hind gut in the form of nitrogenous wastes
Green glands: collect and excrete urine

35. Phylum Echinodermata Means spiny skinned
Includes starfish, sea urchin and sea cucumber
They are radially symmetrical organism, made of 3 germ layers that are solely aquatic.
They have two body openings, a one way digestive system and have a tube –within- a tube body plan
Food is digested exrtacellularly
They reproduce sexually and asexually via regeneration, sexual reproduction is only possible through opposite sexes, there are no hermaphrodites
Fertilization is external
Their nervous system is relatively simple comprising an oral ring and radial nerve cords
Sensory abilities limited to touch and eye spots in some species
They have an open circulatory system and their respiratory system utilizes gills and diffusion through skin
Excretory system made possible by diffusion

36. Why are Arthropod so successful?
1. Most biologically successful and abundant animal group on earth.
2. There are more arthropod species than all other species combined.
3. There are 1 million known species.
4. Symmetry is bilateral.
5. Small coelom.
6. Jointed appendages for efficient locomotion.

37. 7. Exoskeleton that provides:
(a) protection of internal organs
(b) waterproof covering allowing many to live on dry land
8. Segmented body with parts modified and fused to form specific body regions:
(a) head – anterior
(b) thorax - middle
(c) abdomen - posterior

38. 9.Possess a variety of well developed systems:
a) Digestive
b) Respiratory
c) Excretory
d) Reproductive
e) Skeletal
f) Circulatory - open system
g) Nervous - well developed with the following features:
(i) distinct brain
ii) ventral nerve cord
(iii) sense organs such as eyes, auditory organs, sensory bristles, and antennae that touch and sense chemicals

39. Arthropod Exoskeleton
Arthropods have developed a rigid and jointed external skeleton made of a waterproof material known as chitin.
The skeleton provides many advantages including a site for muscle attachment and protection of bodily tissues.
Because Arthropods do grow and because their exoskeletons cannot expand they are forced to periodically shed their exoskeletons. This is called molting

40. Arthropods: Specialized Body Segments
Arthropods have developed three body segments which are often fused
Head
Thorax
Abdomen
Their appendages are attached to these regions providing them with the ability to develop and specialized for specific functions including sensory reception (antennae),feeding, (mouth parts) and locomotion (Legs, swimmerets, wings).
They have evolved in such a way that they`ve adapted to obtain nourishment in a variety of ways, eating both plant and animal tissues. Some may feed on either other insects of different phyla or their own. Some may feed on blood. Mouth parts have also evolved to cope with feeding difficulties such as larger and stronger mandibles fangs and teeth.

41. Modified Mouth parts Sucking Mouthparts
Form a tube that can pierce tissues of plants and animals
ex. Mosquitos butterflies
Madibles, maxillae, and other parts of the pharynx are fused into a needle like structure
Sponging and lapping mouthparts
Labium has a modification at its apex
Ex. fruit and house flies
Have a pair of soft lobes that serve as food channels
lap up food or liquefy with salivary secretions
Chewing mouthparts
Mouthparts adapted for seizing, grasping, and crushing food
Adaptations for herbivores and carnivores¸ strong mandibies, toothed plates
Enzymes are secreted from salivary glands that by way of chemical actions can liquefy food to aid in the chewing process

42. Reproduction
Despite short life spans they reproduce in extremely large numbers. They` ve also adapted various techniques to attract mates including the use Pheromones (enticing odours)
Some also have the ability to produce unfertilized eggs that are capable of growing into adults, a process known as Parthenogenesis

43. Appearance
Many have adapted appearance strategies with an advantage for protection or in some cases attraction
Camouflage: organisms blend in with the environment so it cannot be easily seen
Coloration: organisms seeking to attract or repel prey, warning coloration signalling toxicity
Mimicry: insects adapt to look like another dangerous or poisonous insect

44. Developed Nervous System
Have a larger brain than nearest invertebrate relative (Annelid). May have the ability to see, hear, taste, smell and touch
Have a greater range of responsibility
Social interactions and behaviours
Ants and bees demonstrate a hierarchical social lifestyle, one is required for their survival

45. Social Behaviour of bees
Societies display as caste differentiation there is a clear division of labour
All stages of life are present(larvae, pupa, adults)
Activities are collective, each individual works to benefit the community.
social castes of bees
Queen: single sexually mature female
Drone: sexually mature males that mate with the queen
Workers: sexually inactive females that cars for the colony, feed young gather food and care for the hive
Casts are determined by fertilization and by what larvae are feed
Drones develop parthenogenetically from unfertilized eggs and are haploid
queens and workers develop from fertilised eggs they are diploid
Queens are fed royal jelly produced by workers which contains enzymes that allow queen to sexually mature

46. The most successful class is class Insecta with 900,000 known species
Nearly all are terrestrial with a few fresh
Size range is broad; from 0.25 mm for some species of beetles and up to 30 cm for some tropical moths water and saltwater forms

47. The success of insects is credited to the following reasons:
(1) They are the only invertebrates capable of flying. This allows them to move over great distances to find food, escape predators, and spread to new environments.
(2) There is tremendous variation in how they are adapted for feeding and reproduction, so they can exist in all kinds of environments and obtain nourishment from many sources.
(3) High rate of reproduction and short life cycle. This increases the ability of insects to adapt.
(4) Small in size. This means they don’t need large areas to live.
(5) Social insects
(6) Variations in body form

48. Phylum Chordata

49. There are three basic characteristics that distinguish phylum Chordata from all other animal phyla
(1) The presence of a flexible, rod-like, internal supporting structure called a notochord. It runs the length of the organisms near the dorsal surface. In vertebrates it is replaced during embryonic development by cartilage or bone
(2) The presence of a hollow dorsal nerve cord. This lies just above the notochord. This tube will eventually form the brain and spinal cord of the adult.
(3) Gill slits are present at some time in development. These are paired openings in the wall of the pharynx. In some vertebrates, gill slits are only seen in the embryo. In others such as fish they are present and function during respiration for life

50. Vertebrates
1. They are a subphylum under the Phylum Chordata. This means they possess a dorsal nerve cord, notochord, and gill slits at the embryo stage.
2. Vertebrates are the most numerous (95%) and most complex of all chordates.
3. Possess a backbone. The vertebrae surround and protect the nerve chord. Vertebrae develop from and replaces the notochord.

51. 4.Anterior part of the dorsal, hollow nerve cord is enlarged into a brain (cephalization). The cerebrum has increased in size and is more complex.
5. The body is usually divided into head, neck, and trunk. The head contains the brain and various sense organs.
6. A tail is present at some stage of development.
7. Jointed internal skeleton (endoskeleton).
8. Two pairs of appendages.

52. 9. There is a ventral heart with two to four chambers
9. There is a ventral heart with two to four chambers. The circulatory system is closed, and red blood cells contain hemoglobin to bond to oxygen.
10. In aquatic vertebrates, gas exchange takes place in gills. In land vertebrates, it occurs in the lungs.
11. Large coelom containing increasingly complex organ systems.
12. The body covering, the skin, is made up of at least two layers: the epidermis and the dermis. The skin often forms other structures such as glands, scales, feathers, hair, nails, claws, horns and hoofs.

53. Group includes 7 classes:
VERTEBRATES
Group includes 7 classes:
agnatha (jawless)
chondrichthyes (cartilaginous)
osteichthyes (bony)
amphibia (e.g. frog)
reptilia (e.g. alligator)
aves (e.g. eagle)
mammalia (e.g. human)
FISH

54. Fish are the most numerous and widespread of all vertebrates.
59% salt water
40% freshwater
1% move regularly between salt and fresh water

55. Vertebrate Respiration
Fish are the only vertebrate adapted to live their lives solely in water
Water is source of oxygen for cellular respirtion
Obtain oxygen from water by way of gills
Water travels over and through gills allowing oxygen and carbon dioxide to be exchanged between the water outside their bodies and their blood inside. Counter current exchange
Reptiles, Birds, and mammals
Have lung based respiratory systems used to obtain oxygen from air
Functional units of lungs are known as alveoli
their main function in the lung is to transport oxygen into the blood stream and remove carbon dioxide

56. Amphibians Utilise lungs and their skin to carry out gas exchange
However because their lives commence in water they also utilize gills

57. Vertebrate Circulation
There are 3 types of Circulatory Pathways
Fish
Blood flows through a two chambered heart in a one way circuit pathway
Amphibians and most reptiles
Blood flows through a three chambered heart into a two circuit pathway
Crocodiles, birds and mammals
Blood flows through a four chambered heart that is completely separated into right and left halves.
Right half pumps blood to the lungs (deoxygenated)
Left pumps blood to the rest of body (oxygenated)

59. Vertebrate Reproduction
External
Sperm and egg meet outside the bodies of the parents
Fish and frogs
Internal
Sperm and egg meet inside the bodies of the parents
Reptiles birds and mammals
Reptiles and birds lay eggs
Mammals are the only vertebrate where embryo development occurs internally
Some exceptions duckbill platypus and marsupials

60. Vertebrate Classes

61. Class Agnatha Jawless fish that are smooth and shiny
Approx. 60 species of lampreys and hagfish
Tube shaped, 1 metre long
Have an endoskeleton made of cartilage
Complete digestive system
scavengers and parasites
Hagfish bore holes in dead and dying fish
lampreys often latch on to other fish with their sucker like mouths
respiratory system made of 6-14 Pairs of gills
lack an opercuclum
have a circulatory system composed of a two chambered heart
Nervous system composed of a small brain, 8-10 pairs of cranial nerves and a spinal cord with spinal nerves
reproduce sexually with externally fertilization
Ectothermic
Excretory system composed of 2 kidneys, 2 ureters, a bladder and a urinary opening

62. Class Chondrichthyes Cartilaginous fish Approx. 850 species
Includes sharks, rays and skates
Have scales and a skeleton of cartilage not bone. Flexible
Respiratory system made of 5-7 pairs of gills
Lack an operculum
Complete digestive system
Reproduce sexually with primarily internal fertilization no parental care
Nervous system composed of small brain, 8-10 pairs of cranial nerves, a spinal cord with spinal nerves
Ectothermic
Excretory system composed of 2 kidneys, 2 ureters, a bladder and a urinary opening

63. Class Osteichthyes Bony fish Most numerous of all vertebrates
Approx species
Includes trout and herring
Have skeleton made of bone and a complete digestive system
Have a swim bladder which is an internal organ used fro buoyancy
All have a lateral line
Sense organ that is sensitive to pressure change in the water and can detect nearby movement
Detects vibrations and movements to detect predators and prey
Respiratory system made of gills which are covered by an opercuclum
have a two chambered heart
Reproduce sexually with external fertilization and external development
Ectothermic
Nervous system composed of a small brain, 8-10 Pairs of cranial nerves and a spinal cord with spinal nerves
Excretory system made of 2 kidneys, 2 ureters, a bladder and urinary opening

64. Class Amphibia
Includes approx 4000 species of frogs toads newts and salamanders
Undergo metamorphosis
Change in life stages
Larval stage begin life in water and breathe using gills. Adult stage live life on land and use lungs and skin for respiration
Three chambered heart with little blood mixing
Complete digestive system and a nervous system slightly more developed than that of fish
Reproduce sexually with fertilization and development occurring externally
Ectothermic
Excretory systems made of 2 kidneys, 2 ureters, a bladder, and a cloaca
A common opening for the release of urine and feces

65. Class Reptilia
Approx 4000 species including snakes, alligators, crocodiles, and turtles
Have skin made of keratin which is impermeable to water
Endoskeleton made of bone and cartilage, use lungs to breathe
3 chambered heart and a complete digestive system
Nervous system that is more developed than latter classes of vertebrates
Ectothermic, Excretory system lacks a bladder
Reproduce sexually with fertilization occurring internally while development occurs externally
Reptiles lay eggs that contain 4 vital membranes which aid in development
Chorion
Amnion
Yolk sac
allantois

66. Class Aves Approx 9000 species of birds Three types of feathers
Down: insulation
Contour: Shape and color
Quill: Flight
Structurally adapted for flight have hallow bones that are equipped with air sacs.
Air passes through lungs and air sacs so oxygen ne extracted
Complete digestive system
Circulatory system controlled by a 4 chambered heart with a septum
Blood does not mix
Reproduction is sexual with fertilization occurring internally and development externally
Lay eggs the egg white is an extra protein source for the embryo
Endothermic,
Slightly more developed nervous system and have excretory systems similar to reptiles

67. Class Mammalia Includes humans, monkeys , whales
Have hair and mammary glands
Endoskeleton made of bone and cartilage
Utilize lungs to breathe, obtain oxygen from air
Most developed of all vertebrates
Circulatory system controlled by 4 chambered heart with a septum
endothermic
Excretory system made of 2 kidneys, 2 ureters, bladder and a urethra
Reproduction is sexual with fertilization internal and development occurring both internally and externally
Three types of mammals
Monotremes: lay eggs and incubate like birds (platypus, anteater)
Marsupials: pouched mammals with partial external development and nourished externally (kangaroos , opossums)
Placentals: Placentae and umbilical cord for internal development