REVIEW: Section 1: Human Organization and the chemistry of life A) Chemistry of life I. Elements Cannot be broken down by chemical means and still retain the same chemical and physical characteristics II. Atoms Smallest unit of an element that still retains its chemical and physical characteristics Building blocks of everything!! Made up of subatomic particles proton, neutron, electron Atoms are electrically neutral # of protons = # of electrons mass of the atom = the amount of proton + neutrons (e - ~=0) atomic #= # of protons mass # = # protons+ #neutrons III. Matter Matter = anything that has mass and occupies space 1. Pure substance = 1 or more atoms chemically bonded together a) Molecule = two or more atoms form chemical bonds with each other. b) Compounds = Molecules made up of two or more elements -All compounds are molecules; not all molecules are compounds. i. Ionic compounds held together by attractive forces between + and charges. ii. Covalent compounds formed when elements share electrons in outer orbit. 2. Mixture = 2 or more pure substances physically mixed together 1) Homogenous mixture appears uniform when physically mixed together 2) Heterogeneous mixture non uniform in appearance B) Water and Living things Hydrogen bond = The attraction of a δ+ covalently bonded H atom to a δ- atom in another molecule Six Properties of water: (Due to polarity and hydrogen bonding) 1. liquid at room temperature. 2. Temperature of water rises and falls slowly 3. Water has hi heat of vaporization. 4. Frozen water is less dense than liquid water therefore ice floats. 5. Water molecules are cohesive therefore can fill blood vessels. 6. Like dissolves like.
C) Intro to Molecules of Life: Macromolecules (no reading) 4 major types of macromolecules (Macro = big!) Name Subunits (what molecules it is made of) Carbohydrates monosaccharides (sugar molecules) Proteins Amino acids lipids Glycerol + 3 fatty acids Nucleic acids nucleotides Dehydration synthesis = chemical rxn where subunits (+monomer) join together Hydrolysis = chemical rxn where subunits (monomers) come apart from each other. Subunit + subunit macromolecule + H2O Specialized Nucleotide: ATP = Adenosine Triphosphate ATP is an energy carrier molecule in cells Section 2: The Cell Cells = basic building blocks of all living things. A) Cell theory Cell theory = cell is the basic unit of life. 1) nothing smaller can: reproduce, respond to stimuli, remain homeostatic (stable), grow and develop take in and use material from the environment and adapt to changing environment. 2) All living things are made up of cells 3) New cells arise only from pre-existing cells B) The Human Cell (=eukaryotic animal cell) i. Parts of a human cell (=eukaryotic cell) Be able to label a diagram with cell parts ii. Endomembrane system After processing and modifying proteins and synthesizing phospholipids, the ER forms vesicles in which these molecules are transported to other parts of the cell or the Golgi apparatus. Golgi apparatus modifies proteins and lipids, packages them into vesicles that go to other parts of the cell or to the plasma membrane where they discharge their contents
iii. Lysosomes -Contains digestive enzymes that digest or break apart macromolecules and disease causing agents for intracellular digestion. Mitochondria Converts chemical energy of glucose to ATP in a process called cellular respiration Requires O2 (oxygen), releases CO2 (carbon dioxide) as a waste by-product like breathing this is WHY we breath!! iv. Cilia and Flagella-organelles that move a cell or move stuff past both involved in movement of cell v. Plasma membrane 1) Functions of plasma membrane Keeps cell intact Selectively permeable allows only certain molecules or ions to enter or exit cells 2) Fluid mosaic model of plasma membrane structure (what the plasma membrane is made of) Composed of a phospholipid bilayer Phospholipid bilayer = polar, hydrophilic heads, hydrophobic tails 3) Transport Mechanisms across the plasma membrane a) Passive Mechanisms 1. Diffusion random movement of molecules from an area of high conctrn to an area of low concentration until equally distributed Small lipid soluble molecules, especially gases such as CO2 and O2 can move across the membrane freely 2. Osmosis Diffusion of water across the semipermeable membrane The small size of the H2O molecule and the use of protein channels called aquaporins allows free movement. 3. Facilitated Transport larger molecules and ions transported by protein carriers from side of high concentration to an area of low concentration (works on a concentration gradient)
b) Active Mechanisms: 1. Active transport -molecules move against a concentration gradient from an area of low concentration to an area that is already high concentration. Requires a protein carrier and ATP 2. Endocytosis 3. Exocytosis vi. Cell junctions how cells are joined together 3 main types of junctions 1. adhesion junctions- attach adjacent cells 2. tight junctions connections between plasma membrane proteins of neighbouring cells 3. Gap junctions communication portals Section 3: Tissues, Body Cavities and Membranes A) Tissues 4 major types: connective, muscle, nerve, epithelial i. Connective tissue = fibrous, supportive, fluid I. Fibrous Connective tissue (=loose, adipose, and dense) Loose -Supports epithelium and lines internal organs Adipose -Specialized loose -Stores fat for energy, protection, and insulation. Dense -tendons connect muscles to bones / Ligaments connect bones to bones at joints II. Supportive Connective tissue = cartilage, bone 1. Cartilage a. Hyaline cartilage -Nose, end of long bones and ribs, trachea b. Elastic - i.e., outer ear c. Fibrocartilage -Withstands tension and pressure, i.e., vertebral discs, knee joint 2. Bone a. Compact bone - shafts of long bone b. Spongy bone ends of long bones and surrounding the bone marrow cavity Contains red bone marrow for blood cell production III. Fluid Connective tissue = blood and lymph 1. Blood Fluid matrix (=plasma) Specialized cells (called formed elements)= WBC, RBC, and platelets-all have a specific functions. Transports nutrients and oxygen to tissues, takes metabolic waste and CO2 away, and distributes heat. 2. Lymph -Tissue fluid with white blood cells
absorb excess tissue fluid and solutes absorb fat molecules from small intestine contain WBC to engulf pathogens ii. Muscle tissue = skeletal, smooth and cardiac Type: Skeletal Smooth Cardiac Location: Muscles attached to skeleton Around tubes (viscera and blood vessels) heart Nervous control: Voluntary Involuntary involuntary Function: Movement of body Moves stuff thru Heart beat pumps parts tubes blood thru body iii. Nervous tissue = neurons (nerve cells) and neuroglia Nervous tissue = neurons and neuroglia Neurons = nerve cells 3 parts: Dendrite receives input Cell body organelles, cytoplasm, and nucleus Axon conducts impulse away iv. Epithelial tissue = simple, stratified, glandular Simple epithelial = Single layer - linings of organs, Aids in absorption, Protects, Allows exchange Stratified epithelial = Layers of cells -Outer layer -Protects Glandular Epithelium = Secretes a product -Single celled or Multiple celled glands: Exocrine glands= with ducts / Endocrine glands=without ducts- B) Body cavities: Dorsal (back) and Ventral (front) Dorsal: cranial and vertebral Ventral: thoracic, abdominal, and pelvic C) Membranes a) Mucous membrane -Lines external openings of body, digestive, respiratory, urinary and reproductive systems b) Serous membrane 1) Pleura lines thoracic cavity and covers lungs 2) Pericardium covers heart 3) Peritoneum lines abdominal cavity c) Synovial membranes - Lines cavities of joints d) Meninges - surrounds brain and spinal cord