5th Grade Life Science Vocabulary ‐ circulatory system – the organ system that moves blood through the body ‐ digestive system – the organ system that breaks down food for fuel ‐ excretory system – the organ system that removes wastes from the body ‐ muscular system – the organ system made up of muscles that help the body move ‐ nervous system – the set of organs that uses information from the senses to control all body systems ‐ reproductive system – the set of organs that make it possible for organisms to start the life cycle over again ‐ respiratory system – the organ system that brings oxygen to body cells and removes waste gas ‐ skeletal system – the organ system made up of bones that support the body ‐ organ – a group of tissues that perform a specific function or group of functions ‐ bones – section of skeleton: one of the hard parts forming the skeleton in vertebrate animals ‐ muscles – tissue that allows for body movement ‐ stomach – the digestive organ of vertebrates ‐ small intestine – part of digestive tract; the part of the intestine between the stomach and the large intestine – last section of intestinal tract ‐ blood – red fluid circulating in body: the red fluid that is pumped from the heart and circulates around the bodies of humans and other vertebrates ‐ blood vessel – an artery, vein, or capillary through which blood flows ‐ heart – a hollow muscular organ that pumps blood around the body ‐ brain – organ of thought and feeling: the controlling center of the nervous system in vertebrates, connected to the spinal cord and enclosed in the cranium ‐ nerve – a bundle of fibers forming a network that transmits messages in the form of impulses between the brain or spinal cord and the body's organs ‐ lungs – in air‐breathing vertebrate animals, either of the paired spongy respiratory organs ‐ liver – a glandular vascular organ in vertebrates that secretes bile, stores and filters blood, and takes part in many metabolic functions such as the conversion of sugars into glycogen ‐ kidney – waste‐removing vertebrate organ; either of a pair of organs in the abdomen of vertebrates that filter waste liquid ‐ bladder – bodily sac for liquid or gas ‐ skin – natural layer covering body; the external protective membrane or covering of an animal's body, consisting of the dermis and epidermis and often covered in hair, fur, scales, or feathers