thin layer that surrounds and holds a cell together, decides what can enter or leave a cell
interactions among the populations of a community and non-living things in their enviornment
the study of the interactions among living things and the non-living things in their environment
in horticulture and biology, any organism whose genetic information is identical to that of a "mother organism" from which it was created
is a genetic disorder known to be an inherited disease of the secretory glands, including the glands that make mucus and sweat.
is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms and some viruses
If an organism inherits two alleles that are at odds with one another, and the phenotype of the organism is determined completely by one of the alleles, then that allele is said to be dominant
is a chromosomal disorder caused by the presence of all or part of an extra 21st chromosome.. Often Down syndrome is associated with some impairment of cognitive ability and physical growth as well as facial appearance
the plant or animal tissue rich in such molecules, considered as a food source supplying essential amino acids to the body
A gene that is phenotypically expressed in the homozygous state but has its expression masked in the presence of a dominant gene
the major subdivision of a genus or subgenus, regarded as the basic category of biological classification, composed of related individuals that resemble one another, are able to breed among themselves, but are not able to breed with members of another species
any of various proteins originating from living cells and capable of producing certain chemical changes in organic substances by catalytic action, as in digestion
a simple sugar, is a very important carbohydrate in biology. The living cell uses it as a source of energy
is a type of sugar which is less sweet than glucose. It is considered a nutritive sweetener because it has food energy
a sterol that occurs in all animal tissues, esp. in the brain, spinal cord, and adipose tissue, functioning chiefly as a protective agent in the skin and myelin sheaths of nerve cells
the part of the central nervous system enclosed in the cranium of humans and other vertebrates, consisting of a soft, convoluted mass of gray and white matter
a specialized, impulse-conducting cell that is the functional unit of the nervous system, consisting of the cell body and its processes, the axon and dendrites
one of the system of branching vessels or tubes conveying blood from various parts of the body to the heart.
the oxygen-carrying pigment of red blood cells that gives them their red color and serves to convey oxygen to the tissues
the fluid that circulates in the principal vascular system of human beings and other vertebrates, in humans consisting of plasma in which the red blood cells, white blood cells, and platelets are suspended.
the assignment of organisms to groups within a system of categories distinguished by structure, origin, etc
the combining of the constituent elements of separate material or abstract entities into a single or unified entity