Chapter 1 & 2 Homeostasis & Biochem Flashcards
11 Body Systems
- 1 Integumentary System
- 2 Skeletal System
- 3 Muscular System
- 4 Nervous System
- 5 Endocrine System
- 6 Cardiovacular System
- 7 Lymphatic System/Immunity
- 8 Repiratory System
- 9 Digestive System
- 10 Urinary System
- 11 Reproductive System (Male/Female)
Level’s of understanding
Factual Knowledge
Comprehension
Application
Analysis
Synthesis
Evaluation
What does our body do to maintain life?
- Maintain boundaries
- Movement
- Digestion
- Metabolism
- Excretion
- Reproduction
- Growth
Define Homeostasis
Homeo = same Stasis = standing still
- Maintanence of stable internal environment.
- Homeostatic imbalance is a disturbance to homeostasis resulting in disease.
Homeostasis - 5 steps in the human body
- Stimulus - produces change in variable
- Receptor - detects the change
- Input - information sent along afferent pathway to control center
- Output - information sent along efferent pathway to effector
- Response - response of effector works to reduce the effect of the stimulus and return variable to homeostatic level
Kinetic Versus Potential Energy
Kinetic energy is energy in action
Potential energy is stored energy that is inactive
e.g. body at rest, dam of water
Forms of Energy
Chemical - stored in the bonds of chemical substances
Electrical - is the result of the movement of charged particles
Mechanical - directly involved in moving matter
Radiant - travels in waves, also known as electromagnetic radiation
atoms
each element is comprised of identical particles.
the subatomic particles
nucleus - containing protons(p+) and neutrons(n0) and is positively charged
Protons and Neutrons are both 1amu (atomic mass unit)
electrons (e-) - has a negative charge equal in strength to the positive charge of the proton
atoms have a neutral charge as protons and electrons are always equal
atomic number
the number of protons in the nucleus - written subscript to the left (Hydrogen - 1H)
atomic mass number
sum of the masses of its protons and neutrons (electron size is ignored because it’s so small)
isotopes
structural variations among like elements
Isotopes of elements have the same number of protons and electrons but have a different amount of neutrons.
radioisotopes
these are isotopes that decompose sponteneously in a process called radioactivity
molecule
a combination of two or more atoms held together by a chemical bond
what is a compound?
two ore more different kinds of atoms bind, they form molecules of a compound
e.g. two hydrogen and one oxygen atom form H20
Compounds are chemically pure; all of their molecules are identical. A molecule is the smallest part of a compound.
what is a mixture?
a mixture is a substance composed of two or more components physically intermixed.
Solutions - homogeneous mixtures of components that may be gas, liquid, or solid. (solvent - disolving medium and solutes - disolved into the solvent).
Colloid - emulsions or heterogeneous mixtures - their composition is dissimilar in different ares of the mixture. Solutes do not settle out.
Suspensions - heterogeneous mixtures with large solutes that tend to settle out.
what is a chemical bond?
it is an energy relationship between the electrons of the reacting atoms
where do electrons reside
the electron shell which surround the nucleus of the atom.
The limit currently observed is seven shells.
Each shell has one or more orbitals.
Energy level and electron shell are used interchangably. Each shell represent a different energy level.
Electron Shell limits
the first shell is full with 2 electrons
shell 2 holds 8
shell 3 holds 18
subsequent shells hold more
when are atoms inert?
when the outermost shell is full or contains 8 electrons.
What are the three chemical bonds?
Ionic - formed by the transfer of one or more electrons from atom to the other. Strongest
Covalent - shared electrons occupy a single orbital common to both atoms satisfying the stabiilty needs of each atom. Intermediate
Hydrogen - takes place between a hydrogen atom carrying a partial positive charge and an atom with a partial negative charge. Weakest
What is a chemical reaction?
A chemical reaction occurs whenever chemical bonds are formed, rearranged, or broken.
What are the three types of chemical reaction?
Synthesis (or combination) - always involves bond formation and are the basis of constructive or anabolic activities in the body.
Decomposition - are the reverse of synthesis reactions. Bonds are broken. These underly all catabolic processes in the body.
Exchange (or displacement) - involves both breakdown and synthesis.
What are organic compounds?
They are made by living things, they all contain carbon and are covalently bonded.
What are inorganic compounds?
Generally, compounds that lack carbon.
In the body these are: Water, salts, many acids and bases.
What are the properties of water and what is it’s importance in human biology?
Water is an unparalleled solvent. Biological molecules do not react chemically without a solution and virtually all chemical reactions in the body depend on water’s solven properties.
Hydrolysis is important in food breakdown.
Water cushions around certain organs and helps to protect them.
What is an acid?
Substances that release hydrogen ions (H+) in detectable amounts.
Acids are proton donors.
Taste sour and can “burn” a whole in your rug.
What is a base?
These are proton acceptors. They take up hydrogen ions.
what is an electrolyte?
all ions are electrolytes, substances that conduct an electrical current in a solution.
Types of energy flow in chemical reactions?
Exergonic - yield products with less energy than the initial reactants, along with harvestable energy (i.e. energy that can be put to use elsewhere.
Endergonic - contain more potential energy in their bonds than did the reactants. Anabolic reactions are typically endergonic.
Neutralization
When acids and bases are mixed they neutralize eachother and form water (H20) and salt (NaCl)
What are the buffers of acid base balance in the body?
Kidneys and Lungs help to resist abrupt and large swings in the pH of ody fluids by releaseing hydrogen ions when pH begins to rise and by binding them when pH drops.
A major buffer is the Bicarbonate Buffer System.
macromolecules
large complex molecules containing thousands of atoms
polymers
chainlike molecules made of smaller identical or similar subunits (monomers)
dehydration synthesis
two monomers are joined when one loses a hydrogen atom and the other loses a hydroxl group. The result is the release of water as the two monomers bond
what is hydrolysis?
in these reactions a water molecule is added to each bond that is broken. This releases the building blocks (smaller molecules) from the polymer.
monosaccharides
simple sugars, are single-chain or single ring structures containing three to seven carbon atoms.
disaccharides
double sugar, formed when two monosaccharides are joined by dehydration synthesis
sucrose, lactose, maltose
polysaccharides
polymers of simple sugars linked together by dehydration synthesis. These are ideal storage products because they are large and insoluble.
carbohydrate function
primarily readily available fuel source for cell function
lipids
insoluble in water but dissolve readily in other lipids and in organic solvens such as alcohol and ether.
Triglycerides, phospholipids, steroids
triglycerides
These consist of fatty acids and glycerol
Large molecules, often consisting of hudreds of atoms. The most efficient and compact form of stored energy.
These are composed of fatty acids and glycerol
fats when solid, oils when liquid
Phospholipids
are modified triglycerides
they have two fatty acid chains
the third chain (from triglyceride) is replaced by a phosphate group with an attached nitrogen group
what is the primary form of stored animal sugar?
glycogen
What are some steroid examples?
cholesterol
bile salts
vitamin d
sex hormones
corticosteroids
What are two places that cholesterol is used in the body?
As a component of cell membranes
As a starting molecule for synthesis of all body steroids
bile salts
breakdown products of cholesterol
released by the liver into the digestive tract, they help with fat digestion and absorbtion
What are eicosanoids?
They are diverse lipids derived from faccty acid foun in all cell membranes.
Important for blood clotting, inflammtion, labor contraction and blood pressure.
What are the features of protein?
Proteins are long chains of amino acids joined together by dehydration synthesis.
10-30% of cell mass.
They are structural as well as primary actors in cell function.
Amino Acids and Peptide Bonds?
Amino acids can act as a base or an acid. All of these are identical except for their R group
Amino acids are bound, as protein, in a peptide bond.
United acids form di-peptide, tri-peptide, and polypetides.
Polypeptides can contain 50-10,000 amino acids.
What are 6 roles of proteins in the body?
1 - Structural such as collagen
2 - Enzyme for catalysis - such as disaccharidases hydrolyze disaccharides
3 - Transport - moving substances such as with the blood
4 - Contractile - actin and myosin contract for movement
5 - Communication - Transmitting signals between cells and act as messengers
6 - Defensive proteins protect against disease such as antibodies
Examples of protein structure?
1 - Primary - the sequence of amino acids form the polypeptide chain.
2 - The primary chain forms spirals and sheets
3 - Tertiary structure - the spirals or sheets are then folded up by intramolecular bonds
4 - Quaternary structure - two or more polypeptide chains with tertiary struture combine to form a functional protein.
Two types of proteins and their function?
Globular proteins are functional and at least tertiary in shape or maybe quaternary
Fibrous proteins are structural some have secondary structure but most are tertiary or quaternary.
What has happened to a denatured protein?
It has unfolded and lost its shape.
This occurs because either pH has dropped or temperature has risen above normal physiological levels.
What are enzymes?
Proteins that act as biological catalysts. Or components that regulate or accelerate biochemical reactions.
They can only increase the speed of reactions and do so by a factor of 100,000 to a billion times the rate of an uncatalyzed reaction.
What are two major nucleic acid molecules?
DNA and RNA
What are the structural units of nucleic acids?
Nucleotides
What are the levels of organisation?
- Chemical
- Compound
- Molecular
- Cellular
- Tissue
- Organ
- Organ System
- Organism
When are elements stable or inert?
When their valence shell (outermost) is full of electrons.
