Anatomy and Phisiology

The function of the respiratory system is to supply us with __.

oxygen

The respiratory system removes __ from the body.

carbon dioxide

The heart and blood vessels together move blood around the body, forming the __ system.

cardiovascular

The blood component that carries oxygen is the __.

red blood cells

The protein in red blood cells that carries oxygen is __.

haemoglobin

Diffusion is the movement of molecules from a high concentration to a __ concentration.

low

Alveoli are clusters at the ends of tubes called __.

bronchioles

The lungs are enclosed by two pleural membranes separated by a thin layer of fluid called the __.

pleural fluid

During the cardiac cycle, the phase when the ventricles contract is called __.

systole

The phase when the ventricles relax is called __.

diastole

The blood vessels that carry blood away from the heart and maintain high pressure with thick walls are called __.

arteries

The liquid part of blood is called __.

plasma

The adrenal gland secretes the hormone __ to prepare for action.

adrenaline

The hormone that lowers blood glucose is __.

insulin

Thyroxine from the thyroid gland regulates __.

metabolism

Hormones travel in the blood to target cells; they are produced by __ glands.

endocrine

B-cells produce __.

antibodies

T-cells destroy __ cells.

virus-infected

Phagocytes perform __ to engulf pathogens.

phagocytosis

The outermost layer of skin is the __.

epidermis

The pigment that absorbs UV radiation is __.

melanin

The basic unit of the nervous system is the __.

neuron

The fast conduction in nerves is due to saltatory conduction at the __.

Nodes of Ranvier

Skeletal muscle is connected to bones by __.

tendons

Antagonistic muscle pairs: when one contracts the other __.

relaxes

Osteoblasts build bone; osteoclasts __ bone.

destroy

Synovial joints are lubricated by synovial fluid and surrounded by ligaments; the ends of bones are capped with __.

cartilage

The axial skeleton consists of the skull, spine and ribcage while the __ skeleton consists of the arms, legs, pectoral and pelvic girdles.

appendicular

Growth plates are located at the ends of long bones and their failure results in dwarfism called __.

achondroplasia

Fertilisation occurs in the __.

fallopian tube

The placenta nourishes the fetus via the __.

umbilical cord

The functional unit of the kidney is the __.

nephron

Ultrafiltration moves plasma into Bowman's capsule; the filtrate is called the __.

glomerular filtrate

Substances such as glucose and amino acids are reabsorbed from the glomerular filtrate in the proximal tubule by __ transport.

active transport

ADH stands for __.

antidiuretic hormone

The hormone released during labour to stimulate contractions is __.

oxytocin

After ovulation, the hormone that prepares the uterus is __.

progesterone

The hormone that stimulates the growth of follicles in the ovary is __.

FSH

The organ that produces bile is the __.

liver

The enzyme that digests starch in saliva is __.

salivary amylase

Anatomy

The study of the structures that make up the human body, from cells to organs.

Physiology

The study of how cells, tissues, organs and systems work and function.

Organ system

A group of organs that work together to perform a major body function.

Homeostasis

Maintenance of internal body conditions (temperature, pH, fluids, glucose) through self-regulating feedback.

Negative feedback

A control mechanism that reverses a deviation from the optimum to restore balance.

Positive feedback

A process that amplifies a deviation from the norm, moving further from balance.

Osmoregulation

Regulation of water and electrolyte balance to keep body fluids isotonic.

Islets of Langerhans

Pancreatic cells that monitor blood glucose and secrete insulin or glucagon.

Insulin

Hormone that promotes uptake of glucose by cells, lowering blood glucose.

Glucagon

Hormone that raises blood glucose by converting glycogen to glucose.

Hypothalamus

Brain region that coordinates autonomic and endocrine responses; thermoregulation center.

Pituitary gland

Master endocrine gland that releases hormones under hypothalamic control.

Thyroxine

Thyroid hormone that regulates basal metabolic rate.

Calcitonin

Thyroid hormone involved in calcium balance (calcium regulation).

Adrenaline

Hormone from the adrenal glands preparing body for ‘fight or flight’.

Somatotrophin

Growth hormone; promotes body growth and cell reproduction.

Endocrine gland

Gland that secretes hormones directly into the bloodstream.

Hormone

Chemical messenger produced by glands that acts on distant target cells.

Antigen

Molecule that triggers an immune response (usually a protein or carbohydrate).

Antibody

Protein produced by B-cells that binds specific antigens to help eliminate invaders.

B-cell

Lymphocyte that produces antibodies against specific antigens.

T-cell

Lymphocyte that mediates cellular immunity and helps coordinate immune responses.

Phagocytosis

Process by which phagocytes engulf and digest pathogens or debris.

Phagocyte

White blood cell that performs phagocytosis.

Immunity

The body's ability to resist pathogens through recognition and response.

Epidermis

Outer skin layer; protective, keratinized epithelium with pigment-producing cells.

Dermis

Middle skin layer containing blood vessels, nerves, glands and follicles.

Melanin

Pigment in epidermis that absorbs UV radiation.

Sebum

Oily secretion from sebaceous glands that moisturizes and waterproofs skin.

Sweat gland

Gland that produces sweat to regulate temperature and excrete waste.

Vasodilation

Widening of blood vessels to increase blood flow and heat loss.

Vasoconstriction

Narrowing of blood vessels to reduce blood flow and conserve heat.

Myelin sheath

Insulating layer around many axons; speeds nerve impulse conduction.

Node of Ranvier

Gaps in the myelin sheath where action potentials jump.

Saltatory conduction

Rapid nerve impulse transmission by jumping between Nodes of Ranvier.

Neuron

Nerve cell that conducts electrical impulses.

Dendrite

Branch of a neuron that receives signals from other neurons.

Axon

Long projection that transmits nerve impulses away from the cell body.

Synapse

Junction between neurons where neurotransmitters cross the gap.

Neurotransmitter

Chemical messenger released at synapse to carry nerve impulses.

Alveoli

Tiny air sacs in the lungs where gas exchange with blood occurs.

Pleural membranes

Two membranes around the lungs separated by pleural fluid to reduce friction.

Bronchioles

Small airways that lead to alveoli in the lungs.

Bronchus

Main airway that conducts air into the lungs; part of the respiratory tree.

Trachea

Windpipe; main airway from the larynx to the bronchi.

Diaphragm

Major respiratory muscle that contracts to inflate the lungs.

Intercostal muscles

Muscles between the ribs aiding breathing.

Diffusion

Movement of molecules from high to low concentration across a membrane.

Chyme

Partially digested, semi-fluid mass of food in the stomach.

Villi

Finger-like projections in the small intestine that enlarge surface area for absorption.

Lacteal

Lymphatic vessel in a villus that absorbs fats into the lymphatic system.

Hepatic portal vein

Vein that carries absorbed nutrients from gut to liver for processing.

Bile

Digestive fluid produced by the liver; emulsifies fats to aid digestion.

Pancreas (digestive function)

Organ producing digestive enzymes (amylase, lipase, proteases) and alkaline secretions.

Duodenum

First section of the small intestine where much chemical digestion occurs.

Absorption

Process by which nutrients pass from the gut into the blood or lymph.

Large intestine

Absorbs water and forms solid waste; houses gut bacteria producing vitamins.

Rectum

Final section of the large intestine; stores and expels feces.

Kidney

Organ that filters blood to form urine; maintains fluid and electrolyte balance.

Nephron

Functional unit of the kidney; includes Bowman's capsule, glomerulus and tubules.