Test 1 - Cell, Chemistry, Metabolism Flashcards
Levels of Structural Organization & Body Systems
- Chemical (atoms)
- Cellular (smooth muscle cell)
- Tissue (smooth muscle tissue)
- Organ (stomach)
- System (digestive)
- Organism (people)
Integumentary System
Components
-Skin
-Hair
-Fingernails
-Toenails
-Sweat glands
-Oil glands
Functions
-Helps protect body
-Regulate body temperature
-Eliminates some waste
-Makes vitamin D
-Detects sensations like touch, pain, warmth/cold
-Stores fat and provides insulationSkeletal System
Components
-Bones
-Joints
-Associated cartilages
Functions
-Supports and protects the body
-Provides surface area for muscle attachment
-Aids body movement
-Houses cells that produce blood cells
-Stores minerals and lipidsMuscular System
Components
-Skeletal muscle tissue (usually attached to bones)
-Smooth muscle tissue
-Cardiac muscle tissue
Functions
-Participates in body movements such as walking
-Maintains posture
-Produces heatNervous System
Components
-Brain
-Spinal cord
-Nerves
-Special sense organs like eyes and ears
Functions
-Generates action potentials (nerve impulses) to regulate body activities
-Detects changes in body’s internal and external environments and responds by causing muscular contractions or glandular secretions
Endocrine System
Components
-Hormone-producing glands
-Pineal, hypothalamus, pituitary,
thymus, thyroid, parathyroid, adrenal, pancreas,
ovaries, testes
Functions
-Regulates body activities by releasing hormones (chemical messengers transported in blood from endocrine gland or tissue to target organ)
Homeostasis
A condition of equilibrium, or balance, in the body’s internal environment
Homeostasis is maintained by regulatory processes
The survival of our body cells is dependent on the precise regulation of the chemical composition of their surrounding fluid. This fluid is known as extracellular fluid.
Fluid Compartments
Solids
-Women = 45%
-Men = 40%
Fluids
-Women = 55%
-Men = 60%
-Of the fluids, 2/3 are intracellular fluid, and 1/3 are extracellular fluid made up of 80% interstitial fluid and 20% plasma
Women have more fat on average than males, and males more muscle. Fat has little water content compared to muscle, causing the difference in percentages.
Control of Homeostasis
- Stimulus disrupts homeostasis by increasing/decreasing a
- Controlled condition that is monitored by
- Receptors that send nerve impulses or chemical signals to a (input)
- Control centre that receives the input and provides nerve impulses or chemical signals to (output)
- Effectors that bring about a change or
- Response that alters the controlled condition
Return to homeostasis when the response brings controlled condition back to normal
Homeostasis Imbalances
When homeostasis is disrupted, disease, disorder, and even death may result.
Basic Principles of Chemistry
- Chemistry is the science of structure and interactions of matter
- Matter is anything that has mass and takes up space
- Mass is the amount of matter a substance contains, whereas weight is the force of gravity acting on a mass
Chemical Elements
Matter exists in 3 forms
- Solid - Liquid - Gas
All forms of matter are composed of chemical elements
Elements
Elements are given chemical symbols such as
- O = oxygen - C = carbon - H = hydrogen - N = nitrogen
These elements make up the majority (96%) of our bodies
Atoms
Atoms are the smallest units of matter that retain the properties and characteristics of an element
-Atoms are composed of protons, neutrons, and electrons
Atomic Number and Mass Number
Atomic number is the number of protons in the nucleus of an atom
Mass number is the number of protons and neutrons in an atom
Isotopes
Nearly all elements have two or more structural variations
- Number of protons is always the same - Number of neutrons varies therefore the mass number varies - Number of electrons is always the same - Most isotopes are stable (their nucleus structure doesn't change over time) - Unstable isotopes are called radioisotopes and as their nucleus decays they emit radiation and often transform into a different element
Atomic Mass
The atomic mass/weight of an element is the average mass of all its naturally occurring isotopes
Ions, Molecules, and Compounds
Ion is an atom that has lost or gained an electron
- Cation (+) has lost one electron - Anion (-) has gained one electron
Molecule has 2 or more atoms bonded together
Compound is a substance that can be broken down into 2 or more different elements
Chemical Bonds
Bonds act as powerful “glues” to hold atoms together in molecules
Atoms become chemically stable when their valence (outer) electron shell is full
-1st she’ll holds 2 electrons, others hold 8
Achieve stability by gaining, losing, or sharing electrons
Ionic Bonds
Formed by the transfer of one or more electrons from one atom to another. Mainly found in teeth/bones where they give strength
Covalent Bonds
Atoms share pairs of valence electrons. Most of the body’s structure is made from molecules containing this type of bond. Are strong bonds are the greater the number of shared bonds the stronger the bond
Polar covalent bonds have unequal sharing of electrons
Hydrogen Bonds
Form between or within molecules due to partial charges created by polar covalent bonds involving H. Weak bonds that break/reform easily. Important links in proteins and nucleic acids
Chemical Reaction
A chemical reaction occurs when new bonds are formed or old bonds are broken
- Reactants = starting substances - Products = ending substances
Types of Chemical Reactions
Synthesis (anabolic)
-A + B --> AB
Decomposition (catabolic)
-AB --> A + B
Exchange (anabolic and catabolic)
-AB + CD --> AD + BC
Reversible (products can revert to original reactants)
-A + B ABMixtures
Substances composed of two or more components that are physically blended together, but not bonded together. Most matter in nature exists this way
Solution
-Liquid that contains dissolved substances
Liquid = solvent Substance = solute
-Once mixed together, solutes remain evenly dispersed among the solvent molecules
-Clear because the solute particles are very small
Suspension
-Liquid that contains undissolved substances
-Suspended substances with settle out
-Not clear as the particles are large
Inorganic Compounds
Usually lack carbon and are simple molecules
- Wager is the most important and abundant inorganic compound in all living things - Acids, bases, and salts are also inorganic
Water in Chemical Reactions
Water is the ideal medium
- In a hydrolysis reaction, water is added to break bonds - In a dehydration synthesis reaction, water is removed to make bonds
Acids, Bases, & Salts
Acid
-In water they dissociate in to H+ (hydrogen ions, protons) and anions (protein donors)
Bases
-In water they dissociate into OH- (hydroxyl ions) and cations (proton acceptors)
Salt
-In water they dissociate into cations and anions, neither of which is H+ and OH-
pH
Measure of acid/base concentration
- More H+ --> more acidic - More OH- --> more basic (alkaline)
Organic Compounds
Organic compounds always contain H, usually contain O, and always have covalent bonds
Larger molecules than inorganic a with complex functions
Carbohydrates, lipids, proteins, nucleic acids, and adenosine triphosphate (ATP)
Carbohydrates
Contains C, H, O
Carbohydrates provide most of the energy (ATP) needed for life
About one pound of carbohydrate in the form of glycogen is stored in the body
*excess carbs get stored as fat
Major carbohydrate groups
-Monosaccharides
-Disaccharides
-Polysaccharides
Lipids
Primarily composed of C,H,O, occasionally containing P, N
Not soluble in water
Soluble in nonpolar solvents like alcohol or acetone
Types of Lipids
- Fatty acids - Triglycerides (fats and oils) - Phospholipids - Steroids (cholesterol, bile salts, vitamin D, adrenocortical hormones, sex hormones) - Eicosanoids (prostaglandins, leukotrienes) - Others (carotenes, vitamin E & K, lipoproteins)
Fatty Acids
Building blocks of other lipids
Can be saturated or unsaturated
Catabolized to make energy (ATP)
Triglycerides
Most plentiful lipid in our diet and our body
At room temperature fats (animal origin) are solid and oils (plant origin) are liquid
Composed of glycerol which is a 3 carbon molecule and 3 FA which vary resulting in many different TG molecules
Provide protection, insulation, and energy (ATP)
Phospholipids
Phospholipids are an important component of cell membranes
Polar head, and nonpolar tails.
Steroids
Have 4 rings of carbon atoms
Cholesterol is a steroid (made by the liver, also in our diet) that is used to synthesize other steroids including sex hormones, cortisol, bike salts and vitamin D
Protein
Always contain C, H, O, N, and some some S
More complex in structure and function than carbs or lipids
Proteins give structure to the body, regulate processes, provide protection, assist in muscle contraction, transport substances, and serve enzymes
Amino Acids
Peptides and proteins are formed by combining various amino acids
- Dipeptide = 2 - Tripeptide = 3 - Peptide = 4-9 - Polypeptide = 10-50 - Protein = more than 50
