BIOS 251 / A&P 1 Final Study Guide Latest

BIOS 251 / A&P 1 Final Study Guide
BIOS 251 A&P 1 Final Study Guide
*Spend extra time on the concepts that are in bold*

Don’t forget to study the list of bones and bone features on the Lab Practicum Study Guide!

Ch. 1

Homeostasis

 Condition of equilibrium in the body’s internal environment, and maintained by regulatory processes.
 Survival of our body cells is dependent on the precise regulation of the chemical composition of their
surrounding fluid
 Internal conditions are in a dynamic equilibrium; set point (like thermostat in house)
 Essential for maintenance of life; death and disease.

Components of the homeostatic control loop (feedback loops)

 Negative Feedback: works to oppose change and brings condition back to a set point
o Stimulus > Controlled Condition (blood pressure) > Receptors (baroreceptors in certain blood vessels) >
Control Center (brain) > Effectors (heart & blood vessels) > Response (decrease in HR)
 Positive Feedback: works to enhance change and brings condition further away from a set point (ex. Birth)
o Stimulus > Controlled Condition (stretching of cervix) > Receptors (stretching of cells in cervix) > Control
Center (brain) > Effectors (muscles in wall of uterus) > Response (baby’s body stretches the cervix more)

Ch. 2

Acids and bases

 Acids: ionize into one or more hydrogen ions (H+) and one or more anions (negative ions)
 Bases: dissociate into one or more hydroxide ions (OH-) and one or more cations (positive ions) and are proton
acceptors.

pH scale

 Acidity is lower, alkalinity is higher. Scale is 0-14
 7 is neutral
 Gastric fluid, hydrochloric acid is 0 and 1
 Over cleaner, sodium hydroxide is 13 and 14
 Blood is just over 7

Ch. 3

Tonicity of solutions and their effect on body cells (hypo-, iso-, hypertonic)

 Tonicity of a solution relates to how the solution influences the shape of body cells.
 Isotonic solution = RBC maintain normal shape
 Hypotonic solution = RBC hemolyze
 Hypertonic solution = RBC crenate
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, BIOS 251 / A&P 1 Final Study Guide




Osmosis

 Net movement of water through a selectively permeable membrane from an area of high water concentration to an
area of low water concentration.

Factors that influence the rate of diffusion across the cell membrane

 steepness of the concentration gradient
 temperature
 mass of diffusing substance
 surface area
 diffusion distance

Where DNA may be found in the cell

 Nucleus
 Sometimes in the mitochondria

Where DNA replication occurs in the cell

 Nucleus

Stages of the cell cycle and events at each stage

 Interphase (longest phase)
o G1
 Cell is metabolically active, duplicating organelles, and cytosolic components except for DNA. 8-10
hours.
o S
 DNA replicated. 8 hours
o G2. 4-6 hours.
 Cell growth continues and the cell completes its preparation for cell division
 Mitosis – nuclear division; distribution of two sets of chromosomes, one set into each of two separate nuclei
o PMAT

Stages of mitosis and events at each stage

 Prophase: chromatin condenses and shortens into chromosomes
 Metaphase: centromeres line up at the exact center of mitotic spindle, aka metaphase plate or equatorial plane
region
 Anaphase: the splitting and separation of centromeres and the movement of the two sister chromatids of each pair
toward opposite poles of the cell
 Telophase: begins as soon as chromatid movement stops. Identical sets of chromosomes at opposite poles of the
cell uncoil and revert to their threadlike chromatin form, microtubules disappear or change form, a new nuclear
envelope forms, new nucleoli appear, and the new mitotic spindle eventually breaks.

Ch. 4

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