UNIT 1 EXAM

organization of the body

atom→molecule→macromolecule→organelle→cell→tissue→organ→organ system→organism

anabolism

small molecules joined to form larger ones

catabolism

large molecules broken dow into smaller

characteristics of living things

• metbolism

• growth and development

• responsiveness to stimuli

• regulation (homeostasis)

• reproduction

Integumentary System

• skin + hair

• homeostasis: regulate body temp, protection, synthesizes vitamin D

Skeletal System

• bones + joints

• homeostasis: support, protection, red blood cell production

Nervous System

• Nerves, PNS, CNS, Brain + spinal cord

• homeostasis: responds to sensory+ stimuli+ muscle control+ glands

Muscular System

• muscles + tendons

• homeostasis: produces body movements+ generates heat during contraction

Endocrine System

• glands + hormones

• homeostasis: regulating hormones

Cardiovascular System

• heart+ veins+ arteries

• homeostasis: movement of blood carrying hormones, nutrients, gases and waste

Respiratory System

• lungs+ bronchi+ trachea+ larynx, pharynx+ nose+ nasal cavity

• homeostasis: exchange of gases between blood and air in lungs

Lymphatic System

• lymph nodes + spleen

• homeostasis: transports filters lymph + immune responses

Urinary System

• kidneys+ urinary bladder+ production of urine

• homeostasis: filters blood and expels waste through urine

Digestive System

• oral cavity+ stomach+ liver+ large , small intestines

• homeostasis: digestion, absorption and expel waste

Reproduction System

• male + female repro organs

• homeostasis: reproduction + waste expulsion+ mentration+ pregnancy + childbirth + puberty

homeostasis

maintenance of a relatively stable / consistent internal environment in response to changing internal or external conditions

3 homeostatic mechanism components

• receptor

• control center

• effector

Factors homeostatically regulated

• concentration of nutrients + CO2+ O2 + waste products+ water+ salt + other electrolytes

• pH

• volume + pressure

• temperature

Negative Feedback

• primary control of homeostatic control

• maintains the variable within a ‘normal’ set point

• action is in the opposite direction of the stimulus

Negative Feedback Loop

• stimulus

• receptor

• control center

• effector

• homeostasis

Positive Feedback

• less frequently than negative feedback

• same direction as stimulus

Characteristics of Atom

• nucleus

• protons (+ charge)

• neutrons (neutral charge )

• electrons( - charge)

protons

• positive charge

• number of protons = atomic number

Neutrons

• neutral

• Protons + Neutrons = mass number

Electrons

• Negitive - charge

• move around nucleus

• uncharged atoms: #electrons = #protons

Isotopes

• sma enumber of protons + electrons

• different numbers of neutrons

Electron Shells

• octet rule : eight electrons

• First shell: 2 electrons max

• 2nd + 3rd shell: 8 electrons max

• atoms with complete outer shells are : insert/ stable

Chemical Bonds

• atoms form molecules to fulfill octet rule

• store potential energy

• when broken, energy is released

• 2 types: ionic + covalent

Ionic Bonds

strong mutual attraction between two oppositely charged ions

one atom completely transfers over electrons

Cation

more protons than electrons = overall positive charge

anion

more electrons than protons = overall negative charge

Covalent Bonds

two atoms sharing one or more pairs of electrons

non polar covalent bonds

electrons shared equally

polar covalent bonds

one atom pulls electrons more strongly than the other

hydrogen bond

a weak attraction between polar molecules

one positive being attracted to the negative

Properties of water

• cohesion

• adhesion

• stabilizes temperature

  • takes alot of energy to break apart water molecules

• excellent solvent

  • polar molecules - hydrophilic

  • non polar - hydrophobic

• reduces friction

acids

donate hydrogen ions in water below pH 7

bases

accept hydrogen opns on water above pH 7

pH of blood

7.4

acidosis

pH falls below 7.35

alkalosis

pH above 7.45

buffers

stabilize solutions to their pH

solutions

solvents + solutes

Dehydration Synthesis

• anabolism

• assembles smaller molecules into larger ones

• store energy

Hydrolysis

• decomposition; catabolism

• breaks a molecule into smaller fragments

• release energy

lipids

• insoluble in water

• monomers: fatty acids

• store energy

• structural materials

saturated fatty acids

• tightly compacted

• single covalent bonds between carbons

• solid at room temp

• straight bonds

unsaturated fatty acids

• bent bonds

• carbons form double bonds

• double covalent bonds

• liquid at room temp

triglycerides

• lipid

• adipose tissue

• store energy

• attached to glycerol

lipogenesis

formation of triglycerides when conditions of excess nutrients exist

lipolysis

breakdown of triglycerides when nutrients and energy are needed

phospholipids

• lipid

• two fatty acids tails

• major component of cell membrane

steroids

• lipids

• 4 fused carbon rings

eicosanoids

• modified 20 carbon fatty acids

• local signaling molecules

• inflammatory response

carbohydrates

• monomers: simple sugars

• functions:

  • fuel

  • energy storage

  • structural materials

3 types of carbohydrates

• monosaccharides

  • simple sugars

• disaccharides

  • two simple sugar

• polysaccharides

  • complex carbohydrates

monomers

• fatty acids

• simple sugars

• nucleotides

• amino acids

polymers

• lipids

• carbohydrate

• nucleic acid

• protein / polypeptide

nucleotides

composed of :

• phosphate group

• sugar

• nitrogenous group

DNA

• genetics

• double stranded nucleic acid

• held together by hydrogen bonds

• genetic material found as chromosomes and mitochondria

RNA

• multiple function

• single stranded nucleic acid

• found in nucleus and cytoplasm

ATP

is a high energy nucleotide

Phosphorylation

adding phosphate to a molecule

• atp synthase

dephosphorylation

• removal of phosphate

• ATPase, releasing energy

Proteins

• polypeptide

• have structure

• have defined functions

• catalysts

• chemical messengers

• monomers: amino acids

Protein Structure: Primary structure

• linear sequence of amino acids held together by peptide bonds

Protein Structure: Secondary

• alpha helices and beta sheets

Protein Structure: Tertiary

further folds and bonds form the final three dimensional conformation

Protein Structure: Quaternary

some proetins may be formed by multiple polypeptides/ subunits

denatured

protein loses its shape and no longer functions

Enzymes

• most are proteins

• catalysts to chemical reactions

• active sites

  • help catalyze only one specific reaction

Factors affecting reaction rate

• enzyme concentration

• substrate concentration

• temperature

• pH

• concentration of inhibitor

cofactors

• help enzyme work better

• molecules or ions required

• non protein organic or inorganic structure

metabolic pathways

• typically involve a series of enzymes

• work in sequence

• product = substrate

• regulate through negative feedback

physical barrier

separates cell content (ICF) from surrounding ECF)

slective permeability barrier

controls movement of molecules in and out of cell

electrochemical gradients

separation of charges across the membrane

plasma membrane components

• phospholipids

  • bilayer, most abundent

• cholesterols

  • fluidity+ stability+ lubricant + glue

• proteins

  • carbohydrate chains attached to outer surface

fluid

• fluidity and flexibility form phospholipids and cholesterols

• self seal

mosaic

composed of lipids, proteins and carbohydrates

Plasma membrane proteins

• transport proteins

• cell surface receptors

• identity markers

• membrane bound enzymes

• anchoring proteins

• cell adhesion molecules