Homeostasis/Biological Molecules

Homeostasis

presence of a stable environment (unchanging+ stable)

Parts of a homeostasis loop

Receptor, Control center, Effector

Receptor

Sensitive to a particular environmental change/stimulus

Control center

Receives and processes information from receptor and sends out commands

Effector

responds to command opposing the stimulus

set point

desired value

ex- Thermometer

receptor

ex-Thermostat

Control center

ex-Air condition

Effector

What is negative feedback

An effector activated by the control center opposes the original stimulus

What is feedback

Occurs when receptor stimulation leads to a response that changes the environment at the receptor

Key notes of negative feedback

• Try’s to minimize change

• Brings us back to homeostasis by combatting with a response

• long term control

Positive feedback

an initial stimulus signals a response that exaggerates or enhances the change/stimulus in the original conditions

key notes of positive feedback

• extreme responses

• dangerous or stressful process is to be done quickly before returning to homeostasis

• Short term

Childbirth

Positive feedback

shivering occurs

Negative feedback

Sweating increases

Negative feedback

Blood clotting

Positive feedback

Blood pressure falling

Negative feedback

Suckling milk

Positive feedback

insulin release to blood sugar

negative feedback

Blood vessel

Receptor

Platelets

Control center

Chemicals released

Effector

What is work

Movement of an objct

What is energy

Capacity to perform work

What is kinetic energy

Energy that can transfer to another object to perform work

What is potential energy

energy stored that has the potential to perform work

What is true about energy

• energy is not 100% efficient

• energy is lost as heat

What is activation energy

The amount of energy required to start a reaction

What are enzymes

A protein that lowers activation energy to promote chemical reactions by denaturing

What is a catalyst

Compounds that speed up a chemical reaction

What are organic compounds

Compounds that always contain carbon and hydrogen as their primary structural ingredient

Example of organic compound

Carbs, Lipids, Proteins, Nucleic Acids

What are inorganic compounds

Compounds that don’t contain carbon or hydrogen as their primary structural ingredient

what are examples of an inorganic compound

CO2, H2O, O2, H+, OH-, and NaCl

What are macromolecules

large molecules made of monomer sub units (complex)

What are monomers

molecules that can be bonded to form a polymer

H2O properties

Lubrication, Chemical rxn, high heat capacity, solvent

What is a cation

positive charged ion (ex- Na)

What is an anion

negative charged ion (ex- Cl)

is H2O polar or non-polar

polar

What is an electrolyte

a soluble inorganic compound who’s ions will conduct an electrical current in solution (ex- NaCl)

What is pH

Hydrogen ion (H+) concentration in body fluids which ranges from acidic to basic

What is an acidic solution

A solution that has a pH below 7 —> more H+ than OH- (limes)

What is a basic solution

A solution above a pH of 7 —> more OH- than H+ (ex- bleach)

What is a neutral solution

A solution that has a pH of 7 —> equal parts OH- and H+ (ex- Water)

What is a buffer

Compounds that stabilize the pH solutions by removing or replacing H+ —> helps maintain pH within normal limits

What is carbohydrate

an organic molecule that contains C,H,O in a 1:2:1 ratio

What are monosaccharides

A simple sugar containing 3-7 carbon atoms (glucose, fructose)

What are disaccharides

Two monosaccharides formed together via dehydration synthesis (sucrose)

What are polysaccharides

More complex carbohydrates adding mono/di saccharides to a structure (glycogen)

sterioids

large lipid molecules that share a distinctive carbon-ring framework

Cholesterol

important for plasma membrane and cell growth/division

testosterone

steroid hormone which regulates sexual functions

Phospholipid

• Phosphate group

• non-lipid group

• glycerol

• fatty acid

Glycolipid

• Carbohydrate

• Glycerol

• Fatty acid

Glycerides

The result of a fatty acid attachment