Term | Definition |
Zygote | Cell that forms when a male gamete fertilizes a female gamete |
stem cell | Cell that can divide for long periods of time while remaining undifferentiated |
determination | process by which stem cells become committed to develop into only one type of cell |
differentiation | Process by which committed cells acquire the structures and functions of highly specialized cells |
tissue | Group of cells that work together to perform a similar function. |
Homeostasis | Regulation and maintenance of constant internal conditions |
organ | Group of different types of tissues that work together to perform a specific function or related functions |
organ system | Two or more organs that work in a coordinated way to carry out similar functions |
organism | an individual living things |
species | group of organisms so similar to one another that they can breed and produce fertile offspring. |
Positive feedback | control system in which sensory information causes the body to increase the rate of change away from homoestasis |
negative feedback | Control system for homeostasis that adjusts the body's conditions when the conditions vary from ideal |
Nervous system | Body system that controls sensation, interpretation, and response; includes the brain, spinal cord, and nerves |
endocrine system | Body system that controls growth, development, and responses to the environment by releasing chemical system into the blood stream |
gland | Organ that makes and releases chemicals that affect the activities of other organs |
hormone | chemical signal that is produced in one part of an organism and affects cell activity in another part |
Pituitary | area in the middle of the brain that makes and releases hormones that control cell growth and osmoregulation or water levels in the blood |
thyroid | Gland,which wraps around the windpipe on three sides. It produces hormones that control metabolism, growth, and development. |
CNS | Central nervous system, part of the nervous system that interprets messagesfromothe nerves in the body; includes the brain and spinal cord. |
PNS | Peripheral nervous system, part of the nervous system that transmits impulses between the central nervous system and other organs in the body |
Stimulus | Something that causes a physiological response |
Neuron | Call of the nervous system that sends impulses between the body systems and interprets and stores some messages in the brain |
neurotransmitter | chemical that sends a nervous systems 's signal across a synapse |
Synapse | Tiny gap between neurons through which chemical signals are sent. |
Circulatory system | Body system that transports nutrients and wastes between various body tissues, includes heart, blood, and blod vessels. |
Respiratory system | body system that brings oxygen into the body and removes carbon dioxide ; includes nose, trachea and lungs. |
alveoli | Tiny, thin-walled structures where gas exchange occurs in the lungs. |
trachea | Long structure made of soft tissue that connects the mouth and nose to the lungs in humans |
Diaphragm | thin muscle below the rib cage that controls the flow of air into and out of the lungs. |
Vein | large blood vessel that carries blood from the rest of the body to the heart. |
artery | large blood vessel that carries blood away from the heart. |
capillary | Tiny blood vessels that moves blood between larger blood vessels and other tissues in the body. |
Pathogen | agent that causes diseases |
immune system | body system that fights off infections |
antibody | Protein produced by B cells that helps destroy pathogens |
antigen | protein on the surface of cells, that the immune system uses to identify foreign substances |
vaccine | Substance that stimulated the immune system response; producing acquired immunity without illness or infection. |
inflammation | Immune response that is characterized by swelling, redness, pain, and itching. |
Allergen | antigen that does not cause disease but still produces an immune response. |
digestion | process by which large, complex molecules are broken down into smaller molecules that can be used by cells. |
digestive system | body system that digests food;includes mouth, esophagus, stomach, pancreas, intestines, liver, gallbladder, rectum and anus. |
enzyme | protein that catalyzes chemical reactions for organisms. |
Absorption | process by which nutrients move out of one system into another; e.g. Nutrients moving from the digestive system into the circulatory system. |