seedless vascular plant that produces large fronds; the most advanced group of seedless vascular plants

fertilization

ratio of how much air can be forced out of the lung in one second to the total amount that is forced out of the lung; a measurement of lung function that can be used to detect disease states

joint held together by fibrous connective tissue

type of root system in which the roots arise from the base of the stem in a cluster, forming a dense network of roots; found in monocots

(also, calf bone) parallels and articulates with the tibia

thin stalk that links the anther to the base of the flower

the hormone that binds to a plasma membrane hormone receptor to trigger a signal transduction pathway

series of instinctual behaviors that, once initiated, always goes to completion regardless of changes in the environment

(plural = flagella) long, hair-like structure that extends from the plasma membrane and moves the cell

(also, protonephridia) excretory cell found in flatworms

thin and relatively broad bone found where extensive protection of organs is required or where broad surfaces of muscle attachment are required

movement in which the angle between the bones decreases; opposite of extension

feather specialized for flight

work of breathing performed by the alveoli and tissues in the lung