NEGATIVE FEEDBACK: - Questions And 100% Verified Correct Answers NE...

Ecpi : Anatomy & Physiology Exam: Chapters 1-3 (Actual Questions And 100% Verified Correct Answers

NEGATIVE FEEDBACK:

Effectors return conditions toward normal range.

• Called "negative" bc the response to the change moved the

variable in opposite direction (negative) of the deviation from the set point.

• Most common type of homeostatic mechanism.
• Prevents sudden, severe changes in the body.

- Ex: negative feedback controls body temp., blood pressure,

glucose level in the blood.

POSITIVE FEEDBACK:

Change/deviation is intensified - not reversed. Activity of effector is increased initially, instead of decreasing.

• Uncommon in body / short-lived
• Produce unstable conditions that seem like they will not lead

to homeostasis, but they will.

- Ex: blood clotting and uterus contractions of childbirth.

WHAT IS THE WEAKEST BOND?

Hydrogen bond

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WHAT IS THE STRONGEST BOND?

Covalent bond

CARBOHYDRATES:

•Supply materials to build cell structures.•Water-soluble.•Contain Carbon, hydrogen, oxygen

•Ratio of H to O close to 2:1 (C6H12O6 = glucose)

MONOSACCHARIDES:

- Single sugars: glucose, fructose.

DISACCHARIDES:

- Double sugars: sucrose, lactose.

POLYSACCHARIDES:

- Complex carbohydrates: starch, glycogen, cellulose.

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LIPIDS:

•Insoluble in water, but soluble in organic solvents.•Include triglycerides (fats), phospholipids, steroids.•Important component of cell membranes, and have several functions in cells.

TRIGLYCERIDES (FATS):

• Used for cellular energy.
• Contain more energy per gram than carbohydrates.
• Contain C, H, and O, but less O than carbohydrates.
• Consist of 1 molecule of glycerol and 3 fatty acids.

SATURATED FATTY ACIDS:

Have only single carbon-carbon bonds. Most are solid at room temperature, and of animal origin.

UNSATURATED FATTY ACIDS:

Have one or more carbon-carbon double bond. Most are liquid at room temperature, and are of plant origin.

PHOSPHOLIPIDS: 3 / 4

•Consist of 1 glycerol, 2 fatty acids, and 1 phosphate.•Have hydrophilic Glycerol portion and hydrophobic fatty acid ends.•Major component of cell membranes.

STEROIDS:

• Connected rings of carbon.•Widely distributed in the body, various functions.•Component of cell membranes.•Used to synthesize adrenal and sex hormones.•Cholesterol is the main steroid in the body.

PROTEINS:

• Proteins are used as structural materials, energy source,

hormones, receptors, enzymes, antibodies.

• Proteins consist of building blocks called amino acids.
• An amino acid contains an amino (-N H2) group, a carboxyl

(C O O H) group, and a unique R (side chain) group.

4 LEVELS OF PROTEIN STRUCTURES:

Primary Secondary

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