Classification

1. Classification Fundamentals of Biology

2. Levels of Organization in Living Organisms • Atom – fundamental unit of all matter • Molecule – two or more atoms chemically joined together

3. Levels of Organization in Living Organisms • Organelle – specialized features of cells • Cell – basic unit of life

4. Levels of Organization in Living Organisms • Tissue – group of cells functioning as a unit • Organ – many tissues arranged into a structure with a specific purpose in an organism

5. Levels of Organization in Living Organisms • Organ system – group of organs that work together • Whole organism (individual)

6. Levels of Organization in Living Organisms • Population – group of organisms of the same species occurring in same habitat

7. Levels of Organization in Living Organisms • Community – all species that exist in a particular habitat (ex: all the organisms on a coral reef) • Ecosystem – combination of the community and the physical environment

8. Temperature Control • Ectotherms • Generate body heat metabolically, but cannot maintain constant internal body temperature • Poikilotherms • Body temperature mimics the surrounding environment • Examples: fish, reptiles

9. Temperature Control • Endotherms • Generate body heat metabolically and body temperature does not match the temperature of the surrounding environment • Homeotherms • These organisms retain metabolic heat and can control metabolism to maintain a constant internal temperature

10. Modes of Reproduction • Asexual reproduction • Does not involve mating of two individuals • Young are produce by a single parent organism • The young produced are genetically identical to the parent

11. Modes of Reproduction • Examples of Asexual Reproduction • Fission – the splitting of one organism into two smaller organisms of equal size • Budding – the organism develops buds (small clones) that eventually break off and become another organism • Vegetative reproduction – a plant reproduces new individuals by sending an underground stem (rhizome) sideways from which new plants will sprout

12. Modes of Reproduction • Sexual reproduction • Normally involves two individuals • Parent individuals produce gametes (eggs or sperm) that unite to produce a new, genetically unique individual • Ovaries are the organs that produce eggs • Testes are the organs that produce sperm

13. Modes of Reproduction • Many marine organisms release their eggs and sperm directly into the water, this is known as broadcast spawning. • For broadcast spawning to be effective, millions of gametes must be released into the water at roughly the same time to ensure fertilization will occur • Many broadcast spawning species time the release of their eggs to tides, moon phase, water temperature, etc. to ensure success

14. Modes of Reproduction • Other marine organisms rely on internal fertilization, where a copulatory organ is used to insert sperm directly into the female’s reproductive tract • This method requires contact between parent individuals, but less gametes are required for success

15. Modes of Reproduction • Hermaphrodites – individuals that have male and female reproductive tissues either simultaneously or at different phases during the life. Examples: • Protandry- an individual spends the first portion of the life as a functional male then becomes a female later in life after some cue initiates the change • Protogyny- an individual spends the first portion of the life as a functional female then becomes a male later in life after some cue initiates the change

16. Evolution and Natural Selection • Evolution is defined as a change in the genetic make-up of a population over time • In the wild, any genetically derived traits (such as faster swimming or above-average intelligence) can give one individual survival advantage over others in his/her population.

17. Evolution and Natural Selection • These advantages can be translated into reproductive advantage as well. • If one organism is better survivor, more of their gametes will make it into the next generation in a population. • Those individuals that are less advantaged may not survive to reproduce or will reproduce less. • This is known as natural selection.

18. Evolution and Natural Selection • Natural selection therefore strengthens the gene pool of a species by eliminating less advantageous traits through lack (or reduction) of reproductive events in these individuals.

19. Taxonomy • Taxonomy is the science of classifying and naming organisms. • This classification is done by a variety of methods including DNA and protein analysis, comparing embryos, looking at the fossil record and comparing internal and external body structures.

20. Linnaeus • The first individual to propose an orderly system for classifying the variety of organisms found on our planet was Linnaeus (1753).

21. In his system of classification, the finest unit in the organization of life is the species. • A technical definition of species is a group of interbreeding organisms that do not ordinarily breed with members of other groups

22. How many species are there? • About 1.8 million have been given scientific names.  Thousands more are added to the list every year.  Over the last half century, scientific estimates of the total number of living species have ranged from 3 to 100 million.  The most recent methodical survey indicates that it is likely to be close to 9 million, with 6.5 million of them living on the land and 2.2 million in the oceans.  Tropical forests and deep ocean areas very likely hold the highest number of still unknown species.  However, we may never know how many there are because it is probable that most will become extinct before being discovered and described.

23. Current classification systems have developed from Linnaeus' original work. However, modern classification systems are much more complicated having many levels of hierarchical organization. These systems are also taxonomic(structural and physiological connections between organisms), phylogenic (classification based on genetic connections between organisms), and are structurally based on Darwin's theory of evolution. • Modern classifications of organisms are standardized in a hierarchical system that go from general to specific.

24. Taxonomy • Taxonomy uses several levels of classification shown below from the largest (most species inclusive) to the smallest (only one species): • Domain  Kingdom  Phylum  Class  Order  Family  Genus  Species

26. Distribute • Kingdoms Chart

27. Taxonomy • There can be millions of different organisms in a domain or kingdom, while a species by definition is just one type of organism. • So, what defines a species? Common characteristics and the ability to breed successfully with other members of their species (biological species concept) • For example, there are 7 species of flounder (fish) that exist in the southeast U.S. No matter how much they look alike, they cannot breed with each other and produce viable (functionally reproductive) offspring (reproductive isolation).

28. Phylogenetics • Phylogenetics is defined as the study of evolutionary relationships (relatedness) in organisms. • Biologists may use many factors to determine the relatedness of organisms such as structure, reproductive patterns, embryological or larval development, fossils, behavior or DNA/RNA.

29. Dichotomous key

30. http://anthro.palomar.edu/animal/animal_2.htm

32. Characteristics of animals • 1. Feed • 2. Respiration • 3. Circulation • 4. Excretion • 5. Response • 6. Movement • 7. Reproduction

33. “feed” • Herbivore- eats plants • Carnivore- eats animals • Omnivore- eats plants and animals • Detritivore- feed on decaying organic material • Filter feeders- strain food from water • Parasite- lives in or on another

34. respiration • Lungs, gills, simple diffusion • Take in oxygen and gives off carbon dioxide

35. circulation • Diffusion • Or- circulatory system which includes vessels

36. excretion • Primary waste product is ammonia

37. response • Receptor cells for sound, light, external stimuli

38. movement • Most animals are motile • Some are sessile

39. reproduction • Sexual- genetic diversity • Asexual- increases population number rapidly

40. Kingdom Animalia • Two major groups: • Vertebrates -Invertebrates (97% of all animal species)

41. Invertebrates • Animals without a backbone are known as invertebrates. Those with a backbone are called vertebrates. • About 97% of animals are invertebrates. • All major animal groups have representatives in the marine community. • Several animal groups are exclusively marine.

42. General Characteristics of Animals • Multicellular, diploid organisms with tissues, organs or organ systems in most • Heterotrophic • Require oxygen for aerobic respiration • Reproduce sexually, or asexually, or both • Most are motile at least during some portion of the life cycle • Animal life cycles include a period of embryonic development

43. Body symmetry • Basic body structure: • Symmetry (body plan) • Radial- round; equal parts radiate out from a central point (like that seen in a sea star) • Bilateral- organism can be divided into right and left halves that are more or less equal (ex: marine mammals) • Sponges have no symmetry and are known as asymmetrical.

44. Early development • Zygote- fertilized egg • Blastula- a hollow ball of cells • Blastopore- the blastula folds in creating this opening • Protostome- mouth is formed from blastopore • Deuterosome- anus is formed from blastopore

45. Embryonic germ layers • Cells of animals differentiate into 3 layers • Endoderm- (innermost) develops into the lining of the digestive tract and respiratory tract • Mesoderm- (middle) muscle, circulatory, reproductive, and excretory systems • Ectoderm- (outermost) sense organs, nerves, outer layer of skin

46. Anatomical regions • Anterior- towards head • Posterior- toward tail • Dorsal- back side • Ventral- belly side

47. 1. Phylum Porifera • sponges

48. 2. Phylum Cnidaria • Sea anemones, jellyfishes, corals

49. 3. Phylum Ctenophora • Comb jellies

50. 4. Phylum Platyhelminthes • flatworms