Chapter 2: The Nature of Life Flashcards
(36 cards)
-composition and structure
-growth
-reproduction
-response to stimuli
-metabolism
-movement
-complexity of organization
-adaptation to the environment
attributes of living organisms
progressive increase in size and volume through natural development
growth
the development of new individual organisms through either sexual or asexual means
reproduction
a complex carbohydrate that develops in sieve tubes following an injury; it is commonly associated with the sieve areas of sieve tube members
callose
undifferentiated tissue that develops around injured areas of stems and roots; also the undifferentiated tissue that develops during tissue culture
callus
the cellular breakdown of sugar and other foods, accompanied by release of energy; in aerobic respiration, oxygen is utilized
respiration
the conversion of light energy to chemical energy; water, carbon dioxide, and chlorophyll are all essential to the process
photosynthesis
the breakdown of food molecules
digestion
cellular conversion of raw materials into protoplasm and cell walls
assimilation
one of more than 100 types of matter, most existing naturally but some human-made, each of which is composed of one kind of atom
-98 naturally occurring, 20 human-made
elements
the smallest individual unit of an element
atom
the core of an atom; contains chromosomes and is essential to the regulation and control of all the cell’s functions in a living organism
nucleus
a positively charged particle in the nucleus of an atom
proton
an uncharged particle in the nucleus of an atom
neutron
a negatively charged particle of an atom
electron
the region occupied by electrons around the nucleus
orbital
one of two or more forms of an element that have the same chemical properties but differ in the number of neutrons in the nuclei of their atoms
isotope
the substance when two or more elements are united in a definite ratio by chemical bonds
-ex: table salt (NaCl)
compound
consists of two or more atoms bound together and is the smallest independently existing particle of a compound or an element
-ex: water (H2O)
molecule
the ability of an element to combine with another one, also based on electron number
valence
form when two atoms complete their outermost energy level by sharing a pair of electrons in the outermost orbital
covalent bonds
attraction between oppositely charged atoms
ionic bonds
form as a result of attraction between positively charged hydrogen atoms in polar molecules and negatively charged atoms in other polar molecules
hydrogen bonds
a substance that dissociates in water, releasing hydrogen ions
acid
