Systems unit- Nelson biology 11 definitions

Macromolecule

A very large molecule that’s made up of smaller molecules linked together

Metabolism

The sum total of all of the chemical reactions that occur in an organism

Essential nutrient

A nutrient that cannot be made by the body and must therefore be obtained from food

Monosaccharide

A simple sugar with three to seven carbon atoms

Disaccharide

A sugar made up of two monosaccharide molecules

Polysaccharide

A large molecule made up of many linked monosaccharides

Glycogen

A polysaccharide made up of glucose units

Lipid

An organic compound that does not dissolve in water such as fat or oil

Amino acid

A building block of protein

Peptide bond

A bond that holds together the amino acids in a protein

Polypeptide

A linear chain of several amino acids linked by peptide bonds

Hydrolysis

A chemical reaction in which water breaks apart macromolecules into smaller molecules

Enzyme

A protein molecule that helps speed up important chemical reactions in the body

Alimentary canal

The tube through which food is processed, beginning at the mouth and ending at the anus; also known as the digestive tract

Mechanical digestion

The physical breakdown of large pieces of food into smaller pieces in the mouth by the action of teeth, beak or other similar structures, and by contractions and churning motions in the stomach

Chemical digestion

The chemical breakdown of nutrient molecules into smaller molecules by enzyme action

Salivary glands

Glands in the mouth that produce saliva to begin the chemical digestion of food

Saliva

A watery secretion in the mouth that begins the digestive process

Esophagus

The muscular tube through which food passes from the mouth to the stomach

Peristalsis

A wave like series of muscular contractions through the esophagus

Gastric juice

A mixture of Hydrochloric acid, salts, enzymes, water, and mucus that is produced by glands in the stomach to help digest food

Chyme

A thick liquid produced in the stomach made of digested food combined with gastric juice

Pepsin

An enzyme in gastric juice that helps break down proteins into polypeptides

Duodenum

A short, wide, U-shaped section of the small intestine into which food passes from the stomach

Villi

Finger-like projections lining the surface of the small intestine that increase the surface area to improve the absorption of nutrients

Jejunum

The portion of the small intestine that immediately follows the duodenum

Ilieum

The portion of the small intestine that immediately follows the jejunum

Bile

A greenish yellow fluid secreted bu the liver that helps break down fat (NOT AN ENZYME)

Peptic ulcer

A sore in the stomach lining or duodenum, most commonly caused by an infection with the bacteria “Helicobacter Pylori”

Inflammatory bowel disease

The general name for a group of diseases that cause inflammation in the intestines

Crohn’s disease

A form of inflammatory disease that can affect any part of the alimentary canal from mouth to anus

Ulcerative colitis

A form of Inflammatory disease that attacks the colon

Hepatitis

Inflammation of the liver, most commonly caused by a virus

Cirrhosis

The irreversible replacement of healthy liver tissue with non-functioning scar tissue; most commonly caused by alcohol abuse or hepatitis

Diabetes

A condition in which the body is unable to use glucose for energy

Respiratory system

The group of organs that provide living things with oxygen from outside the body and disposes of waste products such as carbon dioxide

Respiration

All of the processes involved in bringing oxygen into the body, making it available to each cell, and eliminating carbon dioxide as waste

Inspiration

The action of drawing oxygen-rich air into the lungs

Expiration

The action of releasing waste air from the lungs

Gas exchange

The transfer of oxygen from inhaled air into the blood, and of carbon dioxide from the blood into the lungs; it is the primary function of the lungs

Ventilation

The process of drawing, or pumping, oxygen containing medium over a respiratory surface

Diffusion gradient

Describes the relationship in which a dissolved substance moves from a region of high concentration to a region of low concentration

Diaphragm

A sheet of muscle that separates the theocratic cavity from the abdominal cavity

Spirograph

A graph representing the amount and speed of air that’s inhaled and exhaled, as measured by a spirometer

Tidal volume

The volume of air inhaled and exhaled during normal breathing

Inspiratory reserve volume

The volume of air that can be taken into the lungs beyond regular tidal inhalation

Expiratory reserve volume

The volume of air that can be expelled from the lungs beyond the regular tidal exhalation

Vital capacity

The total amount of air that can be moved in and out of the lungs during a single breath

Residual volume

The volume of air that remains in the lungs after a complete exhalation

Pharynx

The passageway just behind the mouth that connects the mouth and nasal cavity to the larynx and esophagus

Trachea

The tube that carries air from the nasal passages/mouth to bronchi and then to the lungs (AKA windpipe)

Glottis

The opening of the trachea through which air enters the larynx

Larynx

The structure between the glottis and the trachea that contains the vocal chords

Bronchus

The passageway that branches from the trachea to the lungs

Bronchiole

The passageway that branches from each bronchus inside the lung to increasingly smaller tubes

Alveoli

A tiny sac, with a wall that is one cell thick, found at the end of a bronchiole; respiratory gases are exchanged here

Hemoglobin

An iron- containing protein found in red blood cells, which binds to and transports oxygen from the lungs to the rest of the body

Tonsillitis

And infection of the tonsils caused by a virus or bacteria

Laryngitis

An inflammation of the larynx that can cause the voice to become raspy or hoarse

Pneumonia

A disease that causes inflammation in one or both lungs; it’s usually caused by a viral or bacterial infection

Bronchitis

A respiratory disease that causes inflammation of the mucous membranes of the bronchi; it’s either acute (from infection) or chronic (from irritant)

Asthma

A lung disease that causes chronic inflammation of the lungs and overproduction of mucus in the lungs

Emphysema

Chronic respiratory disease that affects the ability of the lungs to expel air

Cystic fibrosis

A genetic disease that causes a thick build up of mucus in the lungs, resulting in infection, inflammation, and damage to the lung tissues

Carcinoma

A tumour made up of rapidly multiplying cells

Metastasis

The spread of cancerous cells from their original site to other parts of the body

CAT/CT scan

A specialized x-ray technique used for imaging organs and other tissues in the body (AKA computed axial topography)

Two-photon microscopy

A technique that uses photons from images of living tissue up to a depth of 1 mm.

Bronchoscopy

A technology for viewing, diagnosing, and treating the tissues and organs of respiratory system