Body Structure Key Terms

Question 1

chromatin

Answer 1

Structural component of the nucleus, composes of nucleic acids and proteins. Chromatin condenses to form chromosomes during cell division

Question 2

chromosome

Answer 2

Threadlike structures within the nucleus composed of deoxyribonucleic acid (DNA) that carries hereditary information encoded in genes. Each sperm or egg has 23 unpaired chromosomes. After fertilization, each cell of the embryo has 46 chromosomes (23 pairs). In each pair oh chromosomes, one chromosome is provided by the father and the other by the mother.

Question 3

deoxyribonucleic acid (DNA)

Answer 3

molecule that holds genetic information capable of replicating and producing an exact copy whenever the cell divides.

Question 4

metabolism

Answer 4

sum of all physical and chemical changes that take place in a cell or organism; metabolism includes the building up (anabolism) and breaking down (catabolism) of body constituents.

Question 5

5 levels of organization in the body

Answer 5

cells, tissue, organs, systems and organisms

Question 6

3 main structures of cells

Answer 6

cell membrane, cytoplasm and nucleus

Question 7

cell membrane

Answer 7

acts as a barrier that supports and protects intracellular contents

Question 8

cytoplasm

Answer 8

jellylike matrix of proteins, salts, water, dissolved gases and nutrients

Question 9

organelles

Answer 9

located inside cytoplasm; cellular structure that provides a specialized function such as nucleus (reproduction), ribosomes (protein synthesis), Golgi apparatus (removal of material from cell) and lysosomes (digestion). The membranes of many organelles act as sites of chemical reactions.

Question 10

nucleus

Answer 10

responsible for metabolism, growth and reproduction; carries genetic blueprint of the organism

Question 11

tissue

Answer 11

composed of similar cells that perform specialized or common functions; 4 types of tissue

Question 12

histology

Answer 12

study of tissues

Question 13

4 types of tissues

Answer 13

Epithelial, connective, muscle and nervous

Question 14

epithelial tissue

Answer 14

covers organs, lines cavities and canals, forms tubes and ducts, provides the secreting portions of glands and makes up the outer layer(epidermis) of the skin. It is composed of cells arranged in a continuous sheet consisting of one or more layers.

Question 15

connective tissue

Answer 15

supports and connects other body tissues; various types of connective tissue including cartilage, adipose, bone, elastic fiber and even blood

Question 16

muscle tissue

Answer 16

provides the contractile tissue of the body which is responsible for movement

Question 17

nervous tissue

Answer 17

transmits electrical impulses as it relays info throughout the body

Question 18

organs

Answer 18

body structures that perform specialized functions; composed of two or more tissue types

Question 19

systems

Answer 19

composed of varying numbers of organs and accessory structures that have similar or related functions

Question 20

organism

Answer 20

highest level of organization

Question 21

anatomical position

Answer 21

person stands erect, facing forward and the arms are at the side of the body with the palms facing forward and feet parallel to each another.

Question 22

coronal (front) plane

Answer 22

divides the body into anterior and posterior sections

Question 23

transverse(horizontal) plane

Answer 23

divides the body into top and bottom sections

Question 24

midsagittal plane

Answer 24

runs through center of body, dividing the body into right and left halves