Comparative Anatomy Notes
- 2. 1. Range from Unicellular to Multicellular 2. Autotrophic and/or heterotrophic 3. Life-sustaining functions (energy production, waste removal) range from intracellular means to organelles to structured systems. Living Organisms:
- 3. 1) Multicellular organisms 2) Cells form tissues, tissues form organs, organs form organ systems 3) Heterotrophic – must ingest nutrients 4) Aerobic respiration is used 5) Tissue layers that include ectoderm, endoderm, and sometimes mesoderm What defines an animal?
- 4. Smallest living unit, has the ability to survive and reproduce on its own Cells
- 5. A group of cells that function together for one or more specialized tasks Tissues
- 6. A structure with a definite form and function made up of one or more tissue Organs
- 7. Two or more organs that work together for a common task Organ System
- 8. A means to study the evolution, history and lineages of living organisms What is Comparative Anatomy?
- 9. An adaptation is a change in the genotype (genes) and potentially the phenotype (physical expression of the genes) that enables an organism to survive better Result of a DNA mutation Adaptations
- 10. Similarities between structures or functions of structures represent either a common ancestor (common evolutionary path) or a similar adaptation to an environment Evolution
- 11. “The Survival of the Fittest” Those that have adaptations that enable a higher rate of survival will live to reproduce and thus pass on the desirable trait. Over time these changes/adaptations can lead to new species. Natural Selection
- 12. Similar structures that suggest a similar evolutionary path but could have different functions Homologous Structures
- 13. Similar adaptations to a similar environment, do not mean they are the same structure or suggest a similar evolutionary path Analogous Structures
- 14. Structures that no longer serve a purpose and our remnants of an adaptation that is no longer needed Vestigial Structures
- 15. Takes in and distributes oxygen and nutrients to various parts of body through blood Circulatory
- 16. Transportation of nutrients and wastes can occur by: a. Osmosis and diffusion through cell membranes (unicellular and simple organisms) b. Closed (blood in vessels) and open (blood pumped by heart but diffuses through cells) c. Water Vascular system – a system of using water and canals to move nutrients Variations:
- 17. Absorbs nutrients through cell walls/membranes Digestive
- 18. From simple to complex organisms: intracellular to a simple digestive chamber to formal stomachs to digestive organs (i.e. intestines) Digestive Evolution
- 19. Uses chemicals/hormones to elicit a bodily response Endocrine
- 20. Removes wastes from the body Excretory
- 21. From simple to complex: Diffusion and/or exocytosis through cell membrane to single opening digestive chambers to development of the anus to specialized structures and organs Excretory Evolution:
- 22. Stops and destroys foreign bodies from entering the body and causing damage or sickness Immune System
- 23. Protects the body from the outside world Integumentary
- 24. Provides support and movement for an organism Muscular
- 25. Movement mechanisms: a) Cell based – flagellum, cilia b) Water Vascular System – water used to “pressurize” canals and chambers c) Muscles – from single celled muscles to muscle groups Muscular System Evolution:
- 26. Provides communication throughout the body Nervous
- 27. From simple to complex: Unknown pathways to nerve nets to centralized systems including a brain and nerve cord Nervous System Evolution
- 28. Allows for the replication of the species and thus allows the genes to remain in the population Asexual Reproduction: - Simple organisms - Results in genetically identical offspring via budding, binary fission, and autonomy Sexual Reproduction: - More complex organisms - Results in genetically diverse offspring - Development of secondary sex characteristics Reproductive
- 29. The exchange of gases with the atmosphere Respiratory
- 30. Developed from exchange of gases across cell membranes to gills to pseudo lungs to lungs Respiratory Evolution:
- 31. Provides support and protection to the body Skeletal
- 32. - Hardened structures found within (spicules in sponges) - Complete lack of (jellyfish) - Secreted shells - Endoskeleton vs. Exoskeleton SkeletalVariation: