gas exchange in animals Flashcards
adaptations of fish to allow maximum gas exchange
- gill filaments= create a larger SA for gas exchange
-gill filaments covered in lamellae= further increases SA
characteristics of lamallae to allow gas exchange
-thin surface area to allow shirt diffusion pathway
-lots of blood capillaries to increase SA
what is the counter-current principle and how does it benefit the fish?
-blood and water flow in the opposite direction over the lamellae
- conc of oxygen in the water is higher than of the blood, so oxygen diffuses down the conc gradient, faster diffusion
how are insects adapted to gas exchange?
-air moves in via spiracles, small pores leading to trachea
-trachea breaks off into tracheaoles, which have thin permeable walls that go to individual cells
-carbon dioxide moves down its own concentration gradient into spiracles
-rythmic abdominal movements to move air into spiracles
how are alveoli adapted for gas exchange?
-a thin exchange surface- alveoli epithelium is one cell thick, so theres a short diffusion pathway, speeds up diffusion
-a large surface area-large number of alveoli large SA for gas exchangeho
how does gas exchange on the alveoli?
-oxygen diffuses out of the alveoli across the alveolar epithelium and cappilary epithelium and into haemoglobin in the blood
- carbon dioxide diffuses into alveoli from the blood and is breathed out
how is inspiration taken place?
1)external intercoastal muscles and diagrphram muscles contract
2) this causes the ribcage to move upwards and outwards and the diagphram to flatten, increasing the volume of thoraic cavity
3) as volume of thoraic cavity increases, lung pressure decreases
4) area flows from a area of high pressure to low pressure so air moves down trachea into lungs
5) inspiration is an acitve process requires energy
how is expiration taken place?
1) the external intercostal and diagphram muscles relax
2) ribcage moves downwards and inwards and diagrphram becomes curved
3) volume of thoraic cavity decreases, causing the pressure to increase
4) air is forced down the pressure gradient and out of the lungs
5) doesnt require energy
what is tidal volume?
- volume of air in each breath
what is ventilation rate?
- number of breaths per minute
what pulmanory tuberculosis (TB)?
-soemone is infected with tuverculosis bacteria , immune system builds a wall around the bacteria in lungs, forms small hard lumps known as tubercles
what does the bohr affect show?
-when cells respire they increase the partial pressure of carbon dioxide, this decreases the PH of blood so more oxyhaemoglobin unloads, dissociation curve shifts right, more oxygen is being released
