Organisms Exchange Substances With Their Environment Flashcards
What is “1” referring to?
The superior vena cava
What is 2 referring to?
The right atrium
what is 3 referring to?
The right atrioventricular valve
What is 5 referring to?
The pulmonary valve
What is 6 referring to?
The left ventricle
What is 7 referring to?
The aorta
What is 8 referring to?
The pumonary artery
What is 10 referring to?
The pulmonary vein
What is 11 referring to?
The left bicuspid valve
What is 12 referring to?
The left ventricle
What is 13 referring to?
The aortic valve
What are two features all exchange surfaces that relate to surface area and thickness?
All exchange surfaces are adapted to have a large surface area relative to the volume of the organism and are very thin so that diffusion can occur across a short distance
What are the elements of Gas Exchange in Insects?
Spiracles, Tracheae and Trachioles
What are spiracles?
They are stomata-like structures in the skin/exoskeleton of the insect. They are little holes in the walls of the insect that take up gas.
What are the Tracheae?
They are tubular structures attached to the spiracles. Like the Trachea in the lungs. It transports the gas within the insect.
What are trachioles?
They are like the bronchioles as they branch out from the Tracheae and deliver blood to the tissues of the insect, to exchange the gas.
How are diffusion gradients used in gas exchange in insects?
Different diffusion gradients exist along the length of the tracheal system, with the ends of the trachioles having the lowest concentration of oxygen and the highest concentration of CO2, as a result of nearby respiration, and causing the trachioles to draw oxygen further along the system.
How do insects use muscles to aid gas exchange?
Insects flex their bodies by contracting their muscles. This expands and compresses the system. Air sacs between the tracheae and the trachioles expand and compress. This fluctuating pressure moves air in and out of the body, ventilating the system.
How is water used in gas exchange in insects?
The trachiole ends are filled with water. During periods of intense activity, lactose (from lactic acid) builds up. As lactose is a solute, water is drawn into the cells to rebalance the cells. Therefore the trachioles move the water in the system, and this diffuses by osmosis into the cells, allowing more room for gas in the trachioles, increasing gas exchange.
What are the two substructures in gills and how do they connect?
The gill filaments and the gill lamellae. The Gill filaments look like filaments, or the tentacle-like parts of an anemone. The gill lamellae are located on these filaments, sticking up at a right angle to the filament.
What is the countercurrent flow principle?
In order for sufficient gas exchange to occur in fish, the flow of deoxygenated blood and oxygenated water must be in opposite directions.
Why is the countercurrent flow principle a good adaptation for gas exchange (or superior to concurrent flow)?
In fish, oxygen is gained by diffusion from surrounding water into the bloodstream. If the two streams are going in seperate directions, there will be less steep diffusion gradient, and the reaction will reach equilibrium at a higher oxygen saturation level because of this, as the oxygen saturation levels will increase similarly, meaning more oxygen can be exchanged. In concurrent flow there is a larger concentration gradient, meaning oxygen is exchanged too quickly, and the reaction will reach equilibrium sooner, at a lower oxygen saturation. This means less oxygen is absorbed.
What are the two substructures in gills and how do they connect?
The gill filaments and the gill lamellae. The Gill filaments look like filaments, or the tentacle-like parts of an anemone. The gill lamellae are located on these filaments, sticking up at a right angle to the filament.
What is the countercurrent flow principle?
In order for sufficient gas exchange to occur in fish, the flow of deoxygenated blood and oxygenated water must be in opposite directions.
Why is the countercurrent flow principle a good adaptation for gas exchange (or superior to concurrent flow)?
In fish, oxygen is gained by diffusion from surrounding water into the bloodstream. If the two streams are going in seperate directions, there will be less steep diffusion gradient, and the reaction will reach equilibrium at a higher oxygen saturation level because of this, as the oxygen saturation levels will increase similarly, meaning more oxygen can be exchanged. In concurrent flow there is a larger concentration gradient, meaning oxygen is exchanged too quickly, and the reaction will reach equilibrium sooner, at a lower oxygen saturation. This means less oxygen is absorbed.
From top to bottom, describe the structure of a plant tissue.
Waxy Cuticle, Upper Epidermis, Spongy Mesophyll, Vascular Bundle, Lower Epidermis (with guard cells and stomata), Waxy Cuticle.
What is the analogy you use to remember leaf tissue structure?
A cheese and burger-sausage ception sandwich (obvi plant based version).
Top waxy cuticle= top bun
Upper Epidermis= smooth american cheese (just there for protection, adds no taste (or special function))
Palisade Mesophyll- A lettuce leaf
Spongy Mesophyll- A spongy tofu “burger”, full of air pockets.
Vascular Bundle- Veggie Sausage (in the tofu burger)- contains different dead and alive beans (Xylem and Phloem)
Lower Epidermis- Special, emmental style soya cheese, with holes (stomata) and herb bits (guard cells)
Bottom Waxy Cuticle- Lower Bun
What does the top and bottom waxy Cuticle do?
It waterproofs the leaf and reduces water loss. The lower waxy cuticle contains the stomata.
What does the upper epidermis do?
literally just protects the cell.
What is the role of Palisade Mesophyll?
It is the site of photosynthesis, contains a lot of chloroplasts.
What is the role of Spongy Mesophyll?
Increases the surface area of the cell, as it contains many air pockets, and circulates the gas.
What is the role of the Vascular Bundle?
Contains Xylem and Phloem tissue, to transport water and minerals. It is running through the spongy mesophyll.
What is the role of the lower epidermis?
Contains the guard cells and stomata, so is essential for gas exchange. It also protects the cell.
What is the role of the stomata?
Where uptake of gases from the air occurs. It does this due to the two guard cells beside it opening and closing.
How does the guard cell open and close the stomata?
If the two guard cells on either side of the stomata are turgid, the stomata will be open.
What is the role of the stomata?
Where uptake of gases from the air occurs. It does this due to the two guard cells beside it opening and closing.
How does the guard cell open and close the stomata?
If the two guard cells on either side of the stomata are turgid, the stomata will be open.
what are three reasons that Humans need such a large volume of Oxygen to be taken up by the lungs?
Because we are large organisms, we have many living cells that require the oxygen
Because we maintain a relatively high body temperature, so we have high metabolic/respiratory rates.
How thick is the wall of each alveolus? Why is this helpful?
The wall of each alveolus is never more than 0.3μm. This allows the diffusion pathway between the air in the lungs and the blood in the capillaries to be very short.
How many alveoli are there in each lung? How is this useful?
There are 3 million alveoli in each lung. This creates a very large surface area, so a smaller surface area to volume ratio, which increases the rate of diffusion. The mount of area for gases to diffuse across is useful.
What is the total surface area of alveoli in the lungs?
70㎡
How are the capillaries useful for diffusion from the alveoli (aside from the obvious reasons)?
Each alveolus is covered by a dense network of pulmonary blood capillaries. As deoxygenated blood flows through these capillaries, and the air in the alveoli is oxygenated, this helps create a concentration gradient. They also help create a large surface area.
Where do the pulmonary capillaries surrounding the alveoli run to/from?
they either lead to the pulmonary artery or the pulmonary vein. The capillaries carrying deoxygenated blood lead to the pulmonary artery (go away from the heart), while the capillaries carrying the newly fortified blood lead to the pulmonary veins (go towards the heart).
How do red blood cells function in a way that encourages gas exchange in the alveoli?
As the red blood cells from the pulmonary artery/vein pass through the capillaries on the alveoli, they slow down, allowing them to spend more time in the capillaries, resulting in more diffusion.
What is inspiration?
breathing in
What is expiration?
breathing out
What role does the diaphragm play in inspiration?
The diaphragm contracts and moves downwards.
What role do the external intercostal muscles play in inspiration?
The intercostal muscles (muscles between the ribs) contract, causing the ribcage to move up and out.
How is air sucked into the lungs during inspiration?
When the diaphragm contracts and move downwards and the intercostal muscles cause the ribcage to move up and out, the volume of the lungs increases, causing there to be an excess of empty volume, so the air pressure decreases, so in order to reinstate the air pressure, air is drawn in.
How is water used in the alveoli structure?
The inner surface of the alveoli has a thin layer of water on it. This makes sure that the surface the gases diffuse across is always moist, so any gases can be dissolved before entering the bloodstream.
What role does collagen play in the alveolus structure?
Alveoli are surrounded by a collagen cable. This allows the alveoli to stretch and shrink back to shape, which assists in pulling in and pushing out air.
what do the salivary glands do?
They secrete saliva to help lubricate the food for mastecation and digestion. They also produce salivary amylase.
what does the stomach do?
It stores and digests food. It especially breaks down proteins, as the stomach’s contents has a low pH, so the acid easily breaks up the protein. It has sphinctor muscles at each end to allow it to open for food and keep the stomach acid inside when closed.
what does the pancreas do?
The pancreas is a large gland that secretes pancreatic juice which helps digest food after it leaves the stomach. The pancreas contains proteases, lipases and pancreatic amylase.
what is peristalsis?
The process by which food moves through the digestive system by the contraction of muscles.
What is bolus of food?
food after it is passed through the digestive system.
What does bile do?
Bile neutralises the hydrochloric acid in the stomach and contain bile salts that emulsify lipids. It is secreted from the gall bladder.
what does the ileum do?
secretes digestive enzymes and has a massive surface area due to the epithelial tissue lining being covered in villi (that are covered in micro-villi).
what does the large intestine do?
It absorbs water, in order to re-absorb the water released by digestive enzymes.
How is the saliva important for breaking down carbohydrates?
The saliva contains salivary amylase. In the breakdown of carbohydrates through the digestive system, this amylase breaks down starch into maltose ( a disaccharide).
How is the pancreas important for breaking down carbohydrates?
Pancreatic amylase is secreted by the pancreas into the ileum. When maltose molecules pass through the ileum, this pancreatic amylase breaks down the maltose into alpha glucose.
How are alkaline salts used in the digestion of carbohydrates?
Alkaline salts are secreted into the pancreatic juice in order to make sure that the pancreatic amylase that digests carbohydrates in the digestive system is in an environment with the correct pH.
How do lipases digest lipids?
By breaking the ester bonds.
What products are made when lipases break down lipids?
The lipid (usually a triglyceride) releases fatty acids and monoglycerides (in the case of triglycerides, two fatty acids and a monoglyceride)
What are monoglycerides?
Monoglycerides are a glycerol molecule bonded to a single fatty acid.
What is the question mark indicating?
Whay are these necessary?
Companion cells
As phloem cells do not have mitochondria, so they can not respire for themselves, so they have the companion cells respire for them.
What is the question mark indicating?
How does this interact with companion cells?
The source cells
It moves hydrogen ions and sucrose into the companion cells via facilitated diffusion
What is the question mark indicating?
What is the sucrose concentration and water potential like here?
The sink cells
The sucrose is being used up in respiration, so the sucrose concentration is lower. Therefore, the water potential is more positive.
What are the red dots indicating?
Hydrogen ions and sucrose (both of them travel together)
What is the water potential like at at point A and at point B?
Why?
What does this mean about the hydrostatic pressure?
At point A, the water potential is very low, as there is a large concentration of sucrose that has been transported to the phloem from the source and companion cells.
At point B, there is a high water potetnial, as the sucrose has been used up by respiration in the sink cells.
Therfore, water moves to point A by osmosis and water moves away from point B by osmosis, so the hydrostatic pressure at A becomes high and the hydrostatic pressure at B becomes low.
What does the graph relating to the Bohr Effect look like?
It looks like this dumbass
