Exam 1 - Homeostasis and Basic Human Chemistry

Maintaining internal stability within limits is ___.

Homeostasis

The 3 parts of a control mechanism are ____, ____, ____.

receptor, control center, effector

In thermoregulation, the sweat glands act as the _____.

effector

Blood clotting is an example of _____ feedback.

positive

Glucose dissolved in plasma forms a _____ (type of mixture).

solution

A positively charged ion is a ______; a negatively charged ion is an ______.

cation; anion

Sharing electrons forms a ______ bond.

covalent

Building larger molecules from smaller ones is _______/_______.

synthesis/anabolism

Reactions that release energy are ______ (and are usually _______).

exergonic; catabolic

Reaction rate increases with temperature, concentration, smaller particle size, and _______.

enzymes/catalysts

Why is negative feedback protective?

It reverses changes to stabilize variables

Which mixture type best describes whole blood in a tube and why?

suspension; large cells settle

How does the pancreas help maintain glucose homeostasis?

Insulin lowers, glucagon raises

Homeostasis

Stable internal environment within limits

Receptor

Detects change; sends info to control center

Control center

Interprets/decides (often brain)

Effector

Executes response (sweat glands, muscles)

Negative feedback

Reverses deviation (temp, glucose)

Positive feedback

Amplifies to endpoint (clotting, labor, orgasm)

CHON —> make up 96% of the body

Carbon (18%), Hydrogen (10%), Oxygen (65%), Nitrogen (3%)

Solution

Homogenous; no settling (glucose in plasma)

Colloid

Heterogeneous; no settling (Jell-O)

Suspension

Heterogeneous; settles (blood cells)

Ionic bond

Electron transfer; cation/anion attract (NaCI)

Covalent bond

share electrons; polar vs nonpolar

Synthesis/Anabolism

Build bigger molecules; energy in (endergonic)

Decomposition/Catabolism

Break down; energy out (exergonic)

Enzyme

Protein catalysts; speeds reactions