Organizing principles of human body

1. Organizing principles of human body

2. Hierarchy of Structural Organization Each of these build upon one another to make up the next level: Chemical level Cellular Tissue Organ Organ system Organism

3. Hierarchy of Structural Organization Chemical level Atoms combine to make molecules 4 macromolecules in the body Carbohydrates Lipids Proteins Nucleic acids

4. Hierarchy of Structural Organization Cellular Made up of cells and cellular organelles (molecules) Cells can be eukaryotic or prokaryotic Organelles are structures within cells that perform dedicated functions (“small organs”) http://cmweb.pvschools.net/~bbecke/newell/Cells.html

5. Hierarchy of Structural Organization Tissue Collection of cells that work together to perform a specialized function 4 basic types of tissue in the human body: Epithelium Connective tissue Muscle tissue Nervous tissue www.emc.maricopa.edu

6. Hierarchy of Structural Organization Organ Made up of tissue Heart Brain Liver Pancreas, etc…… Pg 181

7. Hierarchy of Structural Organization Organ system (11) Made up of a group of related organs that work together Integumentary Skeletal Muscular Nervous Endocrine Cardiovascular Lymphatic Respiratory Digestive Urinary Reproductive Circulatory Pg 341 Urinary System

8. Levels of Organization: See figs. 1.3 & 1.4 COHN – 99.5% 99.9% =

9. Hierarchy of Structural Organization Organism An individual human, animal, plant, etc…… Made up all of the organ systems Work together to sustain life

10. The Cell • Cells: • structural and functional units of all living organisms. • building blocks of the human body. • adult human body contains ~ 75 trillion cells. • Each cell type performs specific functions. • ~200 cell types in humans • subcategories of most

11. Common Characteristics of Cells • Perform the general functions necessary to sustain life: • Obtain nutrients and other materials from its surrounding fluids. • Fuel molecules, O2, building blocks, minerals,etc • Dispose of wastes products • Urea (from nitrogen), CO2, metabolic waste • Maintain shape and integrity • Size and shape are related to function • Cell division: • Mitosis: growth and repair • Meiosis: gamete formation

12. Study of Cells • Cytology: study of cells • Microscopic anatomy • Individual cells observable by light microscopy • Subcellular structures observable by electron microscopy. • TEM • SEM • Unit of measure: micrometer (um) • RBC: 7-8um

13. Bilateral Symmetry - left half of the body is a mirror image of the right half. - structures in the median plane are unpaired, but have identical left and right sides.

15. Cells • Parts of a cell • Cell Membrane (or plasma membrane) • Cytoplasm • Cytosol • Organelles • Membranous Organelles • Non-membranous Organelles • Inclusions • Nucleus

16. Plasma (Cell) Membrane • the outer, limiting barrier • separates the internal contents of the cell from external materials.

17. Cytoplasm • general term for all cellular contents located between the plasma membrane and the nucleus.

18. Nucleus • “control center” of the cell • controls protein synthesis • directs the functional and structural characteristics of the cell.

19. Plasma membrane: composition • Lipids • Phospholipids • Head: hydrophilic • Tail: hydrophobic • Form lipid bilayer • Cholesterol • Glycolipids • Carbohydrate component • Part of glycocalyx

21. Plasma membrane: composition • Protein • Integral membrane proteins • Peripheral membrane proteins • Some serve as enzymes, ion channels or receptors • Glycoproteins

22. Fertilization: Four Major Steps • Sperm contacts the egg • Sperm or its nucleus enters the egg • Egg becomes activated and developmentalchanges begin • Sperm and egg nuclei fuse

23. Words to know… • Fuse- to physically join together • Ovum – egg cell (female gamete) • Cleavage – process of cell division during development • Differentiation – the process of forming different kinds of cells from similar cells of the early embryo • Embryo – an organism in an early stage of development • Morula – solid ball of cells formed from cleavage • Blastula – hollow ball of cells formed from cleavage • Gastrula – a hollow ball of cells with an “in pushing” and 3 layers (germ layers)

24. Fertilization

25. The Nuclei Fuse Together

26. Development of the zygote, the study of which is known as embryology or developmentalbiology. • The zygote undergoes a series of mitotic cell divisions called cleavage. • The stages of development are: Fertilized ovum (zygote)  2-cell stage  4-cell stage  8-cell stage  Morula  Blastula  Early Gastrula  Late Gastrula

27. Cleavage (divide via mitosis) forms the 2 cell stage

28. And eventually form a Morula

29. And next, a gastrula

30. The Regents Diagram… • Sperm and ovum • Zygote (fertilized ovum) • 2-cell stage • 4-cell stage • Morula • Blastula • Gastrula

31. Differentiation (Organogenesis) • Organogenesis is the formation of the organs (Organo = organs, genesis = creation) • Arises from the layering of cells that occurs during gastrula stage • The layers are germ layers; they have specific fates in the developing embryo: • Endoderm • The innermost layer • Goes on to form the gut • Mesoderm • In the middle • Goes on to form the muscles, circulatory system, blood and many different organs • Ectoderm • The outermost • Goes on to form the skin and nervous system

32. Late Gastrula Endoderm Ectoderm Mesoderm

33. Differentiation of Primary Germ Layers (from the gastrula)

34. Early Human Development Summary • Meiosis makes sperm in males and ovum in females • Sperm and ovum unite nuclei to form a zygote • Zygote undergoes cleavage and becomes gastrula with 3 germ layers

35. 11 Organ systems different organs work together to provide specialized functions • Body Coverings • Support & Movement • Integration & coordination • Transport • Absorption / Excretion • Reproduction