Module 3 - Exchange & Transport Flashcards
Alveoli
Tiny air sacs that serve as the primary gaseous exchange surface, they consist of thin epithelial cell layer, collagen & elastic fibres
Breathing rate
The no. of breaths per minute
Bronchi
Division of the trachea that lead into the lungs, they are small tubes supported by incomplete rings of cartilage
Bronchioles
Many small divisions of the bronchi, contain smooth muscle to restrict airflow to lungs but don’t have cartilage, they are lined with a thin layer of ciliated epithelial cells
Cartiliage
Strong, flexible connective tissue that supports the walls of the trachea & bronchi, preventing collapse, is found in incomplete ring shape
Ciliated epithelial cells
Specialised cells with tiny hair-like cilia found lining trachea that waft bacteria-containing mucus up to back of throat where it is swallowed
Counter current flow
Adaptation for gaseous exchange in bony fish, blood in gills filaments & water moving over the gills flow in opposite directions, maintaining a steep oxygen concentration gradient
Elastic fibres
Fibres of elastin that allow the alveoli to stretch as air is drawn in & recoil back to normal size, expelling air, found in trachea, bronchi & bronchioles
Exchange surface
Surface over which materials are exchanged from 1 region to another. An effective exchange surface has large SA, thin layers, good blood supply & ventilation to maintain steep diffusion gradient
Expiration
Diaphragm relaxes & reverts to a dome, external intercostal muscles relax, moving ribs down & in
Volume of thorax decreases & thoracic pressure exceeds air pressure, air moves out of trachea
Gill filaments
The main site of gaseous exchange in fish, over which water flows, are found in large stacks, gill plates, & have gill lamellae which provide large SA for exchange
Gill lamellae
Fine branches of gill filaments, are adapted for gaseous exchange by having a large SA & good blood supply
Gill plates
Large stacks of gill filaments
Gills
Organs of gaseous exchange in fish, are contained in a gill cavity & are made up of gill lamellae, gill filaments & gill plates
Goblet cells
Specialised cells that secrete mucus onto trachea lining, mucus traps harmful substances & microorganisms, preventing their entry into lungs
Inspiration
Diaphragm contracts & flattens & external intercostal muscles contract, moving ribs up & out, the volume of thorax increases & thoracic pressure falls below air pressure, air moves into trachea
Internal intercostal muscles
Muscles found between ribs which are responsible for forced exhalation
Mammalian gaseous exchange system
Complex system found in mammals which O2 & CO2 gases are exchanged
Operculum
Flap that covers the gills on bony fish, protects the gills & helps maintain constant stream of water over them
Smooth muscle
Involuntary muscle found in walls of trachea & bronchi, constricts lumen of the bronchi by contracting, reducing airflow to lungs
Spiracles
Small, external openings along thorax & abdomen of most insects, through which air enters & air & water leave the gaseous exchange system, Spiracle sphincters open & close the spiracles to control gas exchange
Spirometer
Device used to examine patterns of breathing & determine different aspects of lung volume
SA:V
SA of object / by volume. Larger the SA:V the smaller the object
Tidal volume
Volume of air breathed in or out of the lungs during a normal breath
Trachea (mammals)
Primary airway which carries air from nasal cavity down into chest, tube supported by incomplete rings of cartilage
