| absorption |
the process through which nutrients are transported from the digestive system into the bloodstream |
| action potential |
a series of voltage changes across a cell membrane |
| adenosine triphosphate |
the body's energy currency |
| aerobic respiration |
a process in which energy (in the form of ATP) is produced in abundant oxygen |
| afferent neurone |
neurones that carry information from sensory organs to the central nervous system; also called sensory neurones |
| alveolus |
a balloon-like structure covered in blood vessels where gas exchange occurs |
| anaerobic respiration |
a process in which energy (in the form of ATP) is produed in the low oxygen conditions |
| anus |
the end of the digestive tract; an opening through which faeces is removed |
| aorta |
the largest artery in the body |
| artery |
a blood vessel that transports blood away from the heart to the body's tissues |
| atrium |
an upper chamber in the heart |
| autonomic nervous system |
the division of the peripheral nervous system that controls involuntary movements |
| biconcave |
curved inwards on both sides |
| bile |
a digestive fluid produced by the liver that helps break down fats |
| bile duct |
a tube that connects the liver and gallbladder to the small intestine |
| biliary tract |
the network of tubes and associated organs that make and transport bile from the liver to the small intestine |
| bladder |
a muscular sac that stores urine |
| blood |
the fluid that delivers nutrients and oxygen to the body's cells |
| blood vessel |
a tube that carries blood throughout the body |
| bolus |
a mass of food and saliva |
| bone |
a strong structure that acts as the framework for the skeleton |
| bone marrow |
soft tissue found in spongy bone |
| brain |
the command centre for the body |
| brainstem |
the structure that connects the brain to the spinal cord |
| bronchi |
the branches from the trachea that lead to the lungs |
| bronchiole |
the next branch of the bronchi |
| bronchus |
a single bronchi |
| capillary |
a tiny blood vessel where gas exchange occurs between the blood and body's tissues |
| capillary bed |
a network of capillaries where gas exchange occurs |
| cardiac muscle |
a type of muscle found in the walls of the heart |
| cardiovascular system |
the body system that transports blood, oxygen and nutrients around the body; also called the circulatory system |
| cartilage |
a flexible tissue that covers the ends of bones to cushion joints |
| cartilage |
a strong connective tissue |
| cellular respiration |
the process by which glucose is converted to energy in the form of adenosine triphosphate (ATP) |
| central nervous system |
the main control centre of the body; includes the brain and spinal cord |
| cerebellum |
the back part of the brain; responsible for coordination and balance |
| cerebrum |
the largest part of the brain; responsible for higher thinking processes and voluntary movement |
| chemical digestion |
the chemical breakdown of food caused by enzymes and acids |
| chondrocyte |
a cartilage cell |
| chyme |
the semi-liquid mixture that forms when food is broken down in the stomach |
| circulatory system |
the body system that transports blood, oxygen and nutrients around the body; also called the cardiovascular system |
| compact bone |
the dense outer layer of bone |
| defecation |
the process of removing waste from the body through the anus |
| depolarisation |
the process by which the membrane potential gets closer to 0 |
| diaphragm |
a large dome-shaped muscle found at the base of the ribcage |
| digestion |
the process by which the body breaks down food into smaller components |
| digestive system |
the body system responsible for breaking down food into a form that the body can use for energy |
| digestive tract |
the long tube and associated organs that start at the mouth and end at the anus; also called the alimetary tract or gastrointestinal tract |
| duodenum |
the first part of the small intestine, where most of the chemical digestion occurs |
| ear |
a sensory organ that detects sound and lets us hear |
| effector |
the target tissue |
| efferent neurone |
neurones that send information from the central nervous system to the muscles and glands; also called motor neurones |
| elastic cartilage |
a type of cartilage that provides strength and elasticity/flexibility |
| endocrine gland |
an organ that produces hormones |
| endocrine system |
the body system that produces hormones; also called the hormonal system |
| erythrocyte |
a type of blood cell that carries oxygen; also called a red blood cell |
| excretion |
the process of removing waste from the body |
| excretory system |
the body system that removes waste from the body in the form of urine; also known as the urinary or renal system |
| eye |
a sensory organ that detects light and lets us see |
| faeces |
solid waste produced by the digestive system |
| fibre |
a single thread |
| fibrocartilage |
a type of cartilage that provides support and absorbs shock |
| filtrate |
a liquid that has passed through a filter |
| filtration |
(in excretion) the process by which waste products, excess water and unwanted small molecules are passively filtered out of the blood and into the kidney tubule |
| ganglia |
clusters of neurone cell bodies |
| gas exchange |
the process through which oxygen moves from the lungs into the bloodstream, and waste gases like carbon dioxide move from the bloodstream to the lungs |
| gastric juice |
a complex acidic mixture of water, hydrochloric acid and digestive enzymes |
| glomerulus |
a tiny network of capillaries inside the nephron |
| glucagon |
a hormone produced by the pancreas that raises blood glucose levels |
| gluconeogenesis |
the process by which new glucose is formed in the liver |
| glycogenesis |
the process by which glucose is converted to glycogen for storage |
| glyconeogenesis |
the process by which glucagon is broken down into glucose for use |
| heart |
a muscular organ that pumps blood throughout the body |
| homeostasis |
the maintenance of a stable internal environment despite external changes |
| hormone |
a chemical substance produced by an endocrine gland that is used to communicate to different parts of the body |
| hyaline cartilage |
a type of cartilage that is found on many joint surfaces to reduce friction |
| hyperpolarised |
when the membrane potential is more negative that its resting potential |
| hypothalamus |
a small structure in the brain that bridges the nervous and endocrine system; it helps regulate body temperature, hunger, thirst and emotions |
| hypoxyapatite |
a mineral composed of calcium phosphate that makes up a large amount of bone |
| ileum |
the third part of the small intestine, where vitamin B12, bile salts and any remaining nutrients are absorbed |
| inert |
non-reactive |
| ingestion |
the process of taking food into the mouth |
| insulin |
a hormone produced by the pancreas that lowers blood glucose levels |
| intercalated disc |
a specialised structure found between cardiac muscle cells |
| intercostal muscle |
a small muscle found between the ribs |
| interneurone |
neurones that link sensory and motor neurones with the centra nervous system |
| jejunum |
the second part of the small intestine, where most of the nutrient absorption occurs |
| joint |
a region where two bones meet |
| kidney |
a bean-shaped organ that filters waste from the blood |
| large intestine |
the part of the digestive system between the small intestine and the anus; also called the colon |
| layrnx |
the voice box |
| leukocyte |
a type of blood cell in the immune system that helps the body fight infection and disease; also called a white blood cell |
| ligament |
a strong band of tissue that holds bones together |
| liver |
a metabolic organ that has a range of important functions in the body, like detoxification through filtration of blood and assisting in digestion |
| lobe |
a division of an organ |
| locomotor system |
the body system that includes the bones, muscles, tendons and ligaments in the body; also called the musculoskeletal system |
| lung |
a spongy, air-filled organ where gas exchange occurs |
| mechanical digestion |
the physical breakdown of food caused by forces of motion |
| medulla oblongata |
the lower part of the brainstem that regulates unconscious processes like heartbeat and breathing |
| membrane potential |
the difference in charge between the inside and outside of the cell |
| microfibril |
a fine fibre |
| midbrain |
the top part of the brainstem that controls eye movement and visual and auditory processing |
| motor neurone |
neurones that send information from the central nervous system to the muscles and glands; also called efferent neurones |
| muscular system |
the body system that provides support and facilitates movement |
| musculoskeletal system |
the body system that includes the bones, muscles, tendons and ligaments in the body; also called the locomotor system |
| nasal cavity |
the space inside the nose through which most of the air filters through on the way into and out of the body |
| negative feedback loop |
a mechanism for regulating internal body conditions where the biological reaction reverses the change caused by a stimulus |
| nephron |
a filtration unit inside the kidney |
| nerve fibre |
a bundle of neurones |
| nerve impulse |
an electrical signal that travels along a neurone |
| nervous system |
the body system that controls the body by processing information and sending signals |
| neurone |
a specialised cell that sends and receives electrical signals; also called a neuron or nerve cell |
| neurotransmitter |
a chemical substance that neurones use to communicate with sensory organs, muscles, glands and other neurones |
| nose |
a sensory organ that detects smells and lets us smell |
| nostrils |
the entry points to the nasal cavity |
| oesophagus |
the tube in the throat that connects the mouth to the stomach |
| oral cavity |
the mouth |
| pancreas |
the organ that produces digestive enzymes, and hormones like insulin and glucagon |
| parasympathetic nervous system |
the divison of the autonomic nervous system that plays a role in the "rest-and-digest" response |
| periosteum |
a thin membrane that covers the surface of bone |
| peripheral nervous system |
the system that helps the central nervous system communicate with the rest of the body |
| peristalsis |
rhythmic smooth muscle contractions that move food through the digestive system |
| pharynx |
the section of the respiratory tract that connects the nasal and oral cavities to the larynx and oesophagus; also called the throat |
| pituitary gland |
a small structure that sits below the hypothalamus and controls many endocrine glands; also called the master gland |
| plasma |
(in blood) the biggest component of blood consisting of water, proteins and other solutes |
| platelet |
a small cell fragment involved in blood clotting; also called a thrombocyte |
| pons |
the middle part of the brainstem that regulates sleep–wake cycles, breathing and facial expressions |
| positive feedback loop |
a mechanism for regulating internal body conditions where the biological reaction amplifies the change caused by a stimulus |
| post-synaptic neurone |
the neurone receiving neurotransmitters |
| pre-synaptic neurone |
the neurone that releases neurotransmitters into a gap |
| propulsion |
the process of moving food through the digestive tract |
| pulmonary circulation |
the part of the circulatory system where blood is transported between the heart and lungs |
| reabsorption |
(in excretion) the process by which essential nutrients and water are returned to the blood from the kidney tubule |
| rectum |
where faeces is stored until it is ready for removal |
| red blood cell |
a type of blood cell that carries oxygen; also called an erythrocyte |
| reflex arc |
a nerve pathway involved in reflex actions |
| repolarisation |
the process by which the membrane potential returns to its resting potential |
| respiratory system |
the body system that brings oxygen into the body and removes waste gases |
| respiratory tract |
the pathway through which air travels into and out of the body |
| saliva |
a fluid produced in the mouth that moistens the food |
| salivary gland |
an organ that produces saliva |
| secretion |
(in excretion) the process by which additional waste products and toxins are actively transported from the blood into the kidney tubule |
| sensor |
something that detects stimuli |
| sensory neurone |
neurones that carry information from sensory organs to the central nervous system; also called afferent neurones |
| sensory organ |
an organ that detects stimuli from the environment |
| sinoatrial node |
the heart's natural pacemaker that is responsible for regulating heartbeat |
| skeletal muscle |
a type of muscle that is attached to bones |
| skeletal system |
the body system that gives the body support and shape, protecting the internal organs |
| skeleton |
the structural frame of the body |
| skin |
a sensory organ that detects touch, temperature and pain |
| small intestine |
the part of the digestive tract between the stomach and the large intestine, composed of the duodenum, jejunum and ileum; where most of the nutrient absorption occurs |
| smooth muscle |
a type of muscle that lines some organs, like the stomach, intestine and blood vessels |
| somatic nervous system |
the division of the peripheral nervous system that controls voluntary movements |
| sphincter |
a ring of muscle at the end of a tube that controls the passage of substances into or out of the tube |
| spinal cord |
the tube of nerve fibres that extends from the brain to the lower back |
| spongy bone |
the lighter, porous outer layer of bone |
| stomach |
the muscular, hollow organ that receives food from the oesophagus |
| striated |
organised in parallel streaks |
| sympathetic nervous system |
the division of the autonomic nervous system that plays a role in the "fight-or-flight" response |
| synapse |
the gap between a neurone and what it is communicating with |
| synovial fluid |
the liquid substance inside a joint that helps it move smoothly |
| systemic circulation |
the part of the circulatory system where blood is transported between the heart and the rest of the body |
| tendon |
a collagen fibre that connects bones to skeletal muscle |
| thermoregulation |
the regulation of internal body temperature |
| thrombocyte |
a small cell fragment involved in blood clotting; also called a platelet |
| tongue |
a sensory organ that detects taste |
| trachea |
a sturdy, cartilage-lined tube that connects the layrnx to the bronchi; also called the windpipe |
| tubule |
a small tube |
| ureter |
a thin tube that connects the kidneys to the bladder |
| urethra |
a tube that carries urine from the bladder out of the body during urination |
| urinary system |
the body system that removes waste from the body in the form of urine; also known as the excretory or renal system |
| urinary tract |
the pathway through which urine is formed and removed from the body |
| urination |
the process of removing urine from the body |
| urine |
a yellowish liquid waste formed through kidney filtration |
| valve |
a structure that controls the flow of a fluid |
| vasoconstriction |
the narrowing of blood vessels |
| vasodilation |
the widening of blood vessels |
| vein |
a blood vessel that transports blood back to the heart from the body's tissues |
| vena cava |
the largest vein in the body |
| ventricle |
a lower chamber in the heart |
| vertebral column |
the chain of bones that protect the spinal cord |
| vesicle |
a capsule containing neurotransmitters |
| villi |
tiny finger-like projections that help increase surface area |
| voice box |
the structure that houses the vocal cords and connects the pharynx to the trachea |
| white blood cell |
a type of blood cell in the immune system that helps the body fight infection and disease; also called a leukocyte |
