Chapter 20

Question 1

Endocrine System

Answer 1

is an internal system of regulation and communication involving hormones and the glands that secrete them

Question 2

Hormones

Answer 2

are chemicals that travel through the body and act as signals to generate a response from target cells

Question 3

Target Cells

Answer 3

a cell that that responds to regulatory signals such as hormones

Question 4

Protein Hormones

Answer 4

cannot cross cell membranes, instead it binds to a membrane receptor

Question 5

Signal Transduction

Answer 5

• chain reaction

- inside the cell that tells the cell what to do

Question 6

Steroid Hormones

Answer 6

bind to receptors inside the cell to trigger the target cell

Question 7

Endocrine Glands

Answer 7

groups of cells or organs distributed throughout the brain and body that secrete hormones

Question 8

Axial Skeleton

Answer 8

ribs, spine, and skull

Question 9

Appendicular Skeleton

Answer 9

limbs, pelvic, and pectoral girdles

Question 10

Compact Bone

Answer 10

densely packed, forms the hard, outer shell of bones

Question 11

Spongy Bone

Answer 11

loosely packed, porous, honeycomb-like, interior

Question 12

Bone Marrow

Answer 12

interior of bone, produces blood cells

Question 13

Osteoblasts

Answer 13

remove calcium from blood during bone deposition process

Question 14

Osteoclasts

Answer 14

add calcium to blood by breaking down and reabsorbing bone tissue

Question 15

Muscle Fibers

Answer 15

composed of bundles of cells that are parallel

Question 16

Sarcomeres

Answer 16

• cells are a series of sarcomeres
• contain interacting actin or thin filaments and myosin or thick filaments
• connected by Z-discs which attach to the thin filaments

Question 17

Actin

Answer 17

a protein found in muscle tissue that, together with myosin, facilitates contraction

Question 18

Myosin

Answer 18

a type of protein filament that, along with actin, causes muscle cells to contract

Question 19

Z-Discs

Answer 19

the border of a sarcomere in muscle

Question 20

Antagonistic Muscle Pair

Answer 20

a set of muscles whose actions oppose each other