Organizing principles of human body

Hierarchy of Structural Organization

Each of these build upon one another to make up the next level:Chemical level CellularTissueOrganOrgan systemOrganism

Hierarchy of Structural Organization

Chemical level Atoms combine to make molecules 4 macromolecules in the body

Carbohydrates Lipids Proteins Nucleic acids

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

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

Hierarchy of Structural Organization

Organ Made up of tissue

Heart Brain Liver Pancreas, etc……

Pg 181

Hierarchy of Structural OrganizationOrgan 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

Levels of Organization:Levels of Organization:

COHN – 99.5%

99.9% =

See figs. 1.3 & 1.4

Hierarchy of Structural Organization

Organism An individual human, animal, plant,

etc…… Made up all of the organ systems Work together to sustain life

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

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

Study of Cells

Cytology: study of cellsMicroscopic anatomy Individual cells observable by light

microscopy Subcellular structures observable by

electron microscopy. TEM SEM

Unit of measure: micrometer (um) RBC: 7-8um

2. 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.

Cells

Parts of a cell Cell Membrane (or plasma membrane) Cytoplasm

Cytosol Organelles

Membranous Organelles Non-membranous Organelles

Inclusions Nucleus

Plasma (Cell) Membrane

the outer, limiting barrierseparates the internal contents of the cell from external materials.

Cytoplasm

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

Nucleus

“control center” of the cell controls protein synthesis directs the functional and structural

characteristics of the cell.

Plasma membrane: composition

Lipids Phospholipids

Head: hydrophilic Tail: hydrophobic Form lipid bilayer

Cholesterol Glycolipids

Carbohydrate component Part of glycocalyx

Plasma membrane: composition

Protein Integral membrane proteins Peripheral membrane proteins Some serve as enzymes, ion channels

or receptors Glycoproteins

Fertilization: Four Major Steps

1.Sperm contacts the egg2.Sperm or its nucleus enters the

egg3.Egg becomes activated and

developmentalchanges begin

4.Sperm and egg nuclei fuse

Words to know…Fuse- to physically join together Ovum – egg cell (female gamete)Cleavage – process of cell division during developmentDifferentiation – the process of forming different kinds of cells from similar cells of the early embryoEmbryo – an organism in an early stage of developmentMorula – solid ball of cells formed from cleavageBlastula – hollow ball of cells formed from cleavageGastrula – a hollow ball of cells with an “in pushing” and 3 layers (germ layers)

Fertilization

The Nuclei Fuse Together

Development of the zygote, the study of which is known as embryology or developmental biology. 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

Cleavage (divide via mitosis) forms the 2 cell stage

And eventually form a Morula

And next, a gastrula

The Regents Diagram…

Sperm and ovum1. Zygote (fertilized ovum)2. 2-cell stage3. 4-cell stage4. Morula5. Blastula6. Gastrula

Differentiation (Organogenesis)

Organogenesis is the formation of the organs (Organo = organs, genesis = creation)Arises from the layering of cells that occurs during gastrula stageThe 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

Late Gastrula

Mesoderm

Endoderm

Ectoderm

Differentiation of Primary Germ Layers (from the gastrula)

Ectoderm

Mesoderm

Endoderm

Nervous system

Skeleton Digestive tract

Epidermis of skin

Muscles Respiratory system

Circulatory system

Liver, pancreas

Gonads Bladder

Early Human Development Summary

Meiosis makes sperm in males and ovum in femalesSperm and ovum unite nuclei to form a zygoteZygote undergoes cleavage and becomes gastrula with 3 germ layers

11 Organ systems different organs work together to provide specialized functions

Body Coverings

Support & Movement

Integration & coordination

Transport

Absorption / Excretion

Reproduction