Bio Ch 31

Question 1

Tissue

Answer 1

composed of specialized cells of the same or similar type that perform a common function in the body

Question 2

Epithelial tissue (epithelium)

Answer 2

consists of tightly packed cells that form a continuous layer; covers surfaces and lines body cavities

Question 3

Basement membrane

Answer 3

thin layer of various types of proteins that anchors the epithelium to the extracellular matrix (often a type of connective tissue)

Question 4

Squamous epithelium

Answer 4

composed of flattened cells; found lining blood vessels and the air sacs of lungs

Question 5

Cuboidal epithelium

Answer 5

cube-shaped cells and is found lining the kidney tubules and various glands

Question 6

Columnar epithelium

Answer 6

has cells resembling rectangular pillars or columns, with nuclei usually located near the bottom of each cell; found lining the digestive tract, where it efficiently absorbs nutrients from the small intestine because of minute cellular extensions called microvilli

Question 7

Gland

Answer 7

can be a single epithelial cell, as in the case of mucus-secreting goblet cells within the columnar epithelium lining the digestive tract, or a gland may contain many cells

Question 8

Exocrine glands

Answer 8

glands that secrete their products into ducts

Question 9

Endocrine glands

Answer 9

glands that have no duct (pituitary, thyroid); secrete hormones internally, so they are transported by the bloodstream

Question 10

Connective tissue

Answer 10

the most abundant and widely distributed tissue in complex animals; diverse in structure and function; 3 components - specialized cells, ground substance, protein fibers

Question 11

Collagen fibers

Answer 11

white fiber in the matrix of connective tissue giving flexibility and strength

Question 12

Reticular fibers

Answer 12

very thin collagen fibers that are highly branched and form delicate supporting networks

Question 13

Elastic fibers

Answer 13

yellow fiber containing elastin, a protein that is not as strong as collagen but is more elastic

Question 14

Fibroblasts

Answer 14

both loose fibrous and dense fibrous connective tissues have cells called this that are located some distance from one another and are separated by a jellylike matrix containing white collagen fibers and yellow elastic fibers

Question 15

Loose fibrous connective tissue

Answer 15

supports epithelium and also many internal organs; its presence in lungs, arteries, and the bladder allows these organs to expand

Question 16

Adipose tissue

Answer 16

serves as the body’s primary energy reservoir

Question 17

Dense fibrous connective tissue

Answer 17

contains many collagen fibers that are packed together; has more specific functions than does loose connective tissue

Question 18

Tendons

Answer 18

connect muscles to bones

Question 19

Ligaments

Answer 19

connect bones to other bones at joints

Question 20

Cartilage

Answer 20

cells lie in small chambers called lacunae (sing. lacuna), separated by a matrix that is solid yet flexible

Question 21

Lacuna (pl. lacunae)

Answer 21

small pit or hollow cavity, as in bone or cartilage, where a cell or cells are located

Question 22

Hyaline cartilage

Answer 22

most common type of cartilage; contains only very fine collagen fibers; found in nose, ends of long bones and ribs; forms rings in the walls of respiratory passages; fetal skeleton also made of this type of cartilage

Question 23

Elastic cartilage

Answer 23

has more elastic fibers than hyaline cartilage; more flexible; found in the framework of the outer ear

Question 24

Fibrocartilage

Answer 24

has a matrix containing strong collagen fibers; found in structures that withstand tension and pressure, such as the pads between the vertebrae in the backbone and the wedges in the knee joint

Question 25

Bone

Answer 25

of all connective tissues, this is the most rigid; consists of an extremely hard matrix of inorganic salts, notably calcium salts, deposited around protein fibers, especially collagen fibers

Question 26

Compact bone

Answer 26

makes up the shaft of a long bone; consists of cylindrical structural units called osteons (Haversian systems)

Question 27

Spongy bone

Answer 27

contains numerous bony bars and plates, separated by irregular spaces; lighter than compact bone; designed for strength; site of red bone marrow

Question 28

Blood

Answer 28

consists of formed elements and plasma; fluid connective tissue located in blood vessels

Question 29

Tissue fluid

Answer 29

internal environment of the body consists of blood and this; blood creates this; blood transports nutrients and oxygen to this and removes carbon dioxide and other wastes

Question 30

Red blood cells

Answer 30

small, disk-shaped cells without nuclei; makes the cell biconcave; contains hemoglobin

Question 31

White blood cells

Answer 31

large, have a nucleus; transparent; nucleus typically looks blue or purple; fight infection

Question 32

Pathogens

Answer 32

some white blood cells are phagocytic and engulf infectious these

Question 33

Platelets

Answer 33

not complete cells; fragments of large cells present only in bone marrow; when a blood vessel is damaged, these form a plug that seals the vessel, and injured tissues release molecules that help the clotting process

Question 34

Lymph

Answer 34

fluid connective tissue located in lymphatic vessels; absorb excess tissue fluid and return it to the cardiovascular system

Question 35

Lacteals

Answer 35

special lymphatic capillaries which absorb fat molecules from the small intestine

Question 36

Muscular (contractile tissue)

Answer 36

composed of cells called muscle fibers, which contain actin and myosin filaments, whose interaction accounts for movement and are also important in the generation of body heat

Question 37

Skeletal muscle

Answer 37

voluntary muscle; attached by tendons to the bones of the skeleton; when it contracts, body parts move; cylindrical, long

Question 38

Striated

Answer 38

having bands; in cardiac and skeletal muscle, alternating light and dark bands produced by the distribution of contractile proteins

Question 39

Smooth (visceral) muscle

Answer 39

cells lacking striations; spindle-shaped; involuntary

Question 40

Cardiac muscle

Answer 40

found only in the walls of the heart; contraction pumps blood and accounts for the heartbeat

Question 41

Nervous tissue

Answer 41

contains nerve cells called neurons and supporting cells called neuroglia

Question 42

Neuron

Answer 42

specialized cell with 3 parts - dendrites, a cell body, and an axon

Question 43

Nerves

Answer 43

fibers bound by connective tissue form these outside the brain and spinal cord

Question 44

Neuroglia

Answer 44

nervous tissue contains these cells in addition to neurons; outnumber neurons 10 to 1; make up approximately half the volume of the organ; primary function to support and nourish neurons; some directly contribute to brain function

Question 45

Organs

Answer 45

composed of 2 or more types of tissues working together to perform a particular function

Question 46

Organ system

Answer 46

contains many different organs that cooperate to carry out a general process, such as the digestion of food

Question 47

Body cavities

Answer 47

vertebrates have 2 main ___ _____; smaller dorsal & larger ventral

Question 48

Skin

Answer 48

2 main regions: epidermis and dermis

Question 49

Subcutaneous layer

Answer 49

AKA hypodermis; found between the skin and any underlying structures, such as muscle or bone

Question 50

Epidermis

Answer 50

made up of stratified squamous epithelium; can be thin or thick

Question 51

Melanocytes

Answer 51

specialized cells in the epidermis that produce melanin, the pigment responsible for skin color

Question 52

Dermis

Answer 52

region of dense fibrous connective tissue beneath the epidermis; contains collagen and elastic fibers

Question 53

Nails

Answer 53

protective covering of the distal part of the fingers and toes, collectively called digits; grow from special epithelial cells at the base of these in the portion called the ___ root

Question 54

Hair follicles

Answer 54

begin in the dermis and continue throughout the epidermis, where the hair shaft extends beyond the skin

Question 55

Oil glands

Answer 55

AKA sebaceous glands; secrete sebum, an oily substance that lubricates the hair within the follicle and the skin itself

Question 56

Sweat glands

Answer 56

present in all regions of skin; on average, a person's skin has about 250,000 of these; tubules that begin in the dermis and either open into a hair follicle, or more often, opens onto the surface of the skin; play a role in modifying body temperature

Question 57

Homeostasis

Answer 57

ability of an organism to maintain a relatively constant internal environment

Question 58

Poikilothermic

Answer 58

cold-blooded; body temperature fluctuates depending on environmental temperature; saves energy but restricts the ability of the species to live in extremely cold or hot environments

Question 59

Homeothermic

Answer 59

warm-blooded; birds and mammals have mechanisms for regulating their body temperature toward an optimum; energetically expensive but provides the evolutionary advantage of being able to adapt to many different environments

Question 60

Negative feedback

Answer 60

primary homeostatic mechanism that keeps a variable, such as the blood glucose level, close to a particular value, or set point

Question 61

Positive feedback

Answer 61

mechanism that brings about a continually greater change in the same direction (ex. contractions in child birth)