Fundamentals of Cell Biology and Biochemistry, Exams of Advanced Education

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HUMAN BIOLOGY EXAM 1

biology - is the study of life what is life? - 1. living things contain nucleic acid, protiens, carbohydrates, and lipds

2. living things are composed of cells
3. Living things grow and reproduce
4. Living things use energy and raw materials
5. Respond to their environment
6. maintains homeostasis
7. adaptive traits what are humans made of? - 1. molecules
8. Cell
9. Tissue
10. Organ
11. organ systems
12. individual
13. population Where do humans fit in the overal scheme of life? - Eukarys Animals Invertabrates and vertabraes Community - All the species in an ecosystem that can interact Ecosystem - A community and its physical environment

Biosphere - The part of the eart that supports life Critical thinking involves - inductive reasoning deductive reasoning inductive reasoning - individual facts lead to a general conclusion deductive reasoning - a general statement leads logically to a specific conclusion, "if, then" Human Science involves - clinical trials epidemiological studies Clinical trials - Use human volunteers after successful, safe initial animal studies

• 3 phases: with increasing numbers before FDA approval
• gold standard Epidemiological - Observe patterns that occur in large populations Gold Standards - double blind placebo-controlled studies How to tell the difference between psuedoscience and science - Is the information consistent with information from other credible sources? How reliable is the source of the information? Were proper scientific procedures employed? Were experimental results properly interpreted? (+ check the methods!) Are there any other possible explanations for the results? Chemistry - is the basis of matter

and life (Biology!) Matter - takes up space and has mass Atoms - units of matter cannot be broken into smaller substances by ordinary chemical means made of protons, neutrons, electrons Element - pure form of matter with only one kind of atom Isotopes - atoms with the same number of protons (and electrons) but different number of neutrons Radioisotopes - are unstable and emit particles or energy Ion - an atom that has gained or lost electrons; has a + or - charge Molecule - two or more atoms that join together by chemical bonds Compound - a molecule made of two or more elements Organic Molecules - contain carbon-carbon bonds Inorganic Molecules - No carbon-carbon bonds electron shells - of an atom are involved in bonding Are complete with 2 electrons in the first "shell" and 8 electrons in successive "shells" Covalent Bonds - shares electrons Equally= nonpolar

Unequally= polar Ionic Bonds - "stick together" due to opposite charges Hydrogen bonds - weak attractions between polar covalent molecules involving hydrogen Hydrophilic - is a solvant found inside and outside cells for polar covalent or ionic molecules Hydrophobic - Avoids non-polar covalent molecules High heat capacity - changes temperature slowly- due to hydrogen bonds High heat of vaporization - energy is released at high temperature when it becomes a gas- due to breaking of hydrogen bonds Solid is lighter than the liquid - due to geometry when frozen pH - the measure of free H+ Water is the medium acid - pH = < Base - pH = > Buffer - a mixture of molecules that keeps the H+ constant through equilibrium Example: H2O + CO2 = H2CO3= H+ + HCO3- pH is extremely important - Affects the shape of proteins (stay tuned) Human blood pH- 7.35- 7.

Classes of biological (organic) molecules - Carbohydrates Lipids Proteins Nucleic acids dehydration synthesis - Large polymer molecules are made from "building block" monomers through hydrolysis - Large biological molecules are broken down by Monosaccharides - carbohydrate monomers Glycerol + fatty acids - monomers for most types of lipids Amino acids - protein monomers Nucleotides - carbohydrate + phosphate + nitrogenous base - nucleic acid monomers Carbohydrates Cn(H2O) n - cell membrane structure + used for energy Monosaccharides - have 3-7 carbons, usually in a ring Disaccharides - 2 connected monosaccharides ex. Lactose = glucose + galactose ex. Sucrose = glucose + fructose Polysaccharides - many monosaccharides that link in different ways that affect our ability to use them ex. starch vs cellulose

Lipids - cell membrane structure + hormones + protection/insulation + store and supply energy Lipids - Various molecular structures but all are partly or totally hydrophobic (insoluble in water) Fats (triglycerides) - glycerol + 3 fatty acids Saturated - maximum number of H atoms due to all single bonds; are solid at room T Unsaturated - fewer than maximum number of H atoms due to one or more double bonds; usually liquid at room T Essential fatty acids (EFAs) - 2 you must eat Alpha linolenic (ALA)- an omega- Linoleic- an omega- Omega-3 and omega-6 fatty acids - The first double bond is either 3 or 6 carbons up from the end of the fatty acid molecule A healthy intake ratio is 2:1 omega 6: omega 3; most Americans 10: Trans fats - hydrogens are on the opposite side of the double bond; increase cardiovascular disease risk phospholipids - glycerol and 2 fatty acids (nonpolar) + phosphate group (polar) amphipathic - (hydrophobic + hydrophilic parts) phospholipids - Spontaneously organize in body fluids to make the fabric of the cell membrane! Steroids - Are NOT formed by dehydration synthesis Are formed from 4 carbon ring structures

Example is cholesterol- component of cell membrane + precursor to steroid hormones Proteins - cell membrane (channels and receptors) + enzymes + hormones + supply energy Amino acids - 21 Vary only in their side chain Can be polar or nonpolar; affect protein shape Essential amino acids (9) must be eaten Protiens - form by dehydration synthesis of amino acids Final Shape is specific (Protiens) - depends on interactions among the "R" groups ( +, - or uncharged) of the linked amino acids How many different levels of protien structure - 4 catalysts - speed reactions without being used up in the process Enzymes - Are Catalysts Substrate - Active site joins with _____? Temperature and pH - Enzymes are very sensitive to _____ Nucleic acids - self-replicate + make cell proteins + provide energy nucleotide - monomer- 3 parts Sugar- ribose (RNA) or deoxyribose (DNA) Phosphate

Nitrogenous base- adenine (A), guanine (G), cytosine (C) + uracil (U; in RNA only) or thymine (T; in DNA only) RNA/ DNA - 2 types of nucleic acids made by dehydration sythesis RNA - One strand of linked nucleotides (A,G, C, U) Have ribose sugar DNA - Double strand of linked nucleotides (A, G, C, T); strands linked by hydrogen bonds Have deoxyribose sugar ATP (adenosine triphosphate) - a specialized nucleotide Ribose + adenine (A) + 3 phosphate groups Energy currency of the cell Breaking the terminal bond releases energy Metabolism of food provides energy to remake ATP (stay tuned!) Cell Theory - Cells are the smallest unit of life All living things consist of one or more cells New cells come from other cells Plasma membrane/ Mosaic Structure - All cells have ___ with ____ Fluid Mosaic - Constantly in motion Always moving and changing "colors" = protiens lipids - cholesterol + others

carbohydrates - outer surface, connected to proteins and lipids Functions of plasma membranes - Compartmentalize Controls movement of substances Cell-cell recognition Communication Cell- Cell binding compartmentalization - inside vs outside of cell Controls movement of substances - selectively permeable Cell-cell recognition - via surface glycoproteins communication - protein receptors Cell-cell binding - cell adhesion molecule internal - Most cells have ____ membranes diffusion - higher to lower concentration Facilitated diffusion - uses a carrier protein Osmosis - diffusion of water across a semipermeable membrane From hypotonic to hypertonic solutions No net movement if isotonic solutions Active transport - from lower to higher concentration using a carrier protein

Endocytosis - membrane surrounds a substance outside the cell and brings it in Exocytosis - membrane-bound compartment inside cell joins with outer membrane and expels substance Prokaryotic - Bacteria and archaea External plasma membranes Eukaryotic - All other living things External and internal plasma membranes Nucleus - Contains the nucleoplasm; everything outside it is the cytoplasm Contains the chromosomes (46; 23 pairs); usually in the unraveled form of chromatin Surrounded by a double membrane nuclear envelope with nuclear pores Nucleolus- site of formation of ribosomes RER- rough ER - Has ribosomes attached Makes proteins for export from the cell or incorporation into membranes Note: free ribosomes make proteins for use inside cell SER-Smooth ER - No ribosomes Detoxify alcohol and drugs Produce phospholipids for membranes Golgi Complex - Receives proteins from the RER, modifies, and "packages" them into vesicles

Sends them to the cell membrane for structure or export May bud off as lysosomes Lysosome - Has digestive enzymes- the "stomach of the cell" Kills bacteria and recycles old cell parts Metabolism - all the chemical reactions in the body Anabolism - Building complex molecules from simpler ones Takes energy (ATP) Catabolism - Breaking complex molecules into simpler ones Releases energy (than can be harnessed to make Aerobic - ATP is made by catabolism based on the breakdown of glucose with oxygen Anaerobic - ATP is made by catabolism by glucose without oxygen Aerobic respiration - Requires Oxygen NAD and FAD- function like "electron buses" NAD+ + electrons <-> NADH FAD + electrons <-> FADH Yields about 36 ATP per molecule of glucose glycolysis - Glucose is converted to pyruvate in the cytoplasm

Makes 2 ATP directly Makes NADH Transition reaction - Occurs in the mitochondrial matrix Releases CO Makes NADH Pyruvate is changed to acetyl CoA Citric Acid Cycle - occurs in the mitochondrial matrix Forms ATP directly Forms NADH Forms FADH Releases CO Electron transport chain - on the mitochondrial cristae Drives ATP formation by electron transfer Oxygen is the last electron acceptor and becomes water Anaerobic respiration (fermentation) - Occurs in the cytoplasm only when there is no oxygen Makes a net 2 ATP per molecule of glucose Glucose - is changed into pyruvate Makes 2 ATP + NADH Pyruvate - is changed into lactic acid NAD+ is reformed when electrons are added along the pathway Oxygen debt - lactic acid can be changed back to pyruvate by the liver and channeled through the aerobic pathway when oxygen becomes available

homeostasis - Organ systems work together to allow life and to maintain Epithelial tissue - Lines internal and external surfaces Classified by height and number of layers connective tissue - Most abundant type Binds and supports other tissues Provides transport (blood) and energy storage (fat) Cells are in an extracellular matrix loose (areolar) connective tissue - widespread packing material + adipose tissue (fat) Adipose - fat Dense - Tendons Ligaments Tendons - Muscle to bone Ligaments - bone to bone Specialized - cartilage bone blood Cartilage - semisolid bone - solid

blood - liquid Fibroblasts - in loose and dense connective tissue Adipocytes - in fat Chondrocytes - in cartilage Osteoblasts - make bone Osteoclasts - break down bone Erythrocytes + leukocytes + platelets - blood cells Erythrocytes - red blood cells Leukocytes - white blood cells platelets - cell fragments Skeletal - Striated; voluntary Moves bones and diaphragm cardiac - Striated; involuntary Heart movement (beating) Smooth - Unstriated; involuntary Moves internal organs, blood vessels

Nervous Tissue - Found in brain, spinal cord, and nerves Neurons/Neuroglia - two times of nervous tissue cells Neurons - Nerve cells Neuroglia - support, insulate, and protect the neurons more numerous Tight junction - creates a barrier Adhesion junctions - Hold cells together Gap Junction - Allow cell-to-cell communication organ - two or more tissues that work together for a specific function; ex. the heart- for pumping blood Organ system - two or more organs that work together for a specific function; ex circulatory system= heart + blood vessels 11 - ___ major organ systems homeostasis - the ability of the body to maintain balance around a set point What Homeostasis maintains - Internal core temperature Internal pH Blood pressure Blood levels of important molecules and ions-What

Negative feedback - homeostasis uses ____ to keep things relatively constant in the face of internal and external environmental changes Receptor, Control center, Effector - Negative feedback involves..... Receptor - dectects change Control Center - responds in relation to a set point Effector - cause the response that returns the factor to the set point, is often a muscle or gland Positive feedback - Occurs rarely Is NOT homeostatic Results in an increase in response with each stimulus until an end point is reached Ex. Uterine contractions, oxytocin, and birth ( Axial Skeleton - Skull, vertebral column, ribs Protects the brain, spinal cord, and thoracic organs Appendicular Skeleton - Pectoral and pelvic girdles Anchor for the arms and legs Support Movement Protection of organs Mineral Storage

Fat storage blood cell production - Function of the skeleton Movement - muscle attachment Mineral storage - homeostasis of calcium and phosphorus via osteoblasts and osteoclasts Fat Storage - in yellow bone marrow Blood cell production - in the red bone marrow (ribs, vertebrae, skull, pelvis, ends of long bones) 208 + cartilage - Skeleton is made of __ bones and ___ Bone - Dynamic, living tissue Compact and spongy - 2 types of bones Compact - outer part of all bones + shafts of long bones Spongy - small, flat bones, ends of long bones Proteim matrix - ____ becomes mineralized with calcium phosphate all cartilage - Skeleton of an embryo is ____ ; gradually becomes bone Epiphyseal (growth) plates - growth of long bones is by growth at _____ cartilage cells divide and elongate the bone some cartilage is converted into bone when all cartilage becomes bone, growth stops; steroid hormones involved

Joints - junctions between bones Fibrous - connected by fibrous connectivce tissue; very little movement Cartilaginous - between vertebrae, ribs and sternum, pubic symphysis; little or no movement Synovial - Easy movement in various planes Hinge Ball and socket Hinge - one plane ball and socket - all planes Fibroblasts and Osteoblasts - heal bones Arthritis - inflamed joints Osteoarthritis - degeneration of cartilage at joint Rheumatoid arthritis - Autoimmune attack of the synovial membrane osteoporosis - low bone density