Exchange Of Materials Flashcards
The movement of water is ……. And requires ……. Energy from the cell
Random
No
Osmosis is the diffusion of water across what?
Partially permeable membrane
What type of membrane is the cell membrane
Partially permeable
What may cells nee dot absorb
Substances which are in short supply, against the concentration gradient
What is active transport
The process cells use to absorb substances across partially permeable membranes against the concentration gradient using energy
Where does the e edgy for active transport come from
Respiration
Where can cells absorb ions from
Dilute solutions
How do root cells absorb mineral ions
Active transport
What can the kidney tubules do with active transport
Glucose can be reabsorbed I. The kidney tubules by active transport
Why does active transport require energy
The particles are being absorbed against a concentration gradient
What is dehydration
When the cells are lacking water and mineral ions
Why is glucose used during respiration.
Glucose is released in the process of respiration
If you exercise for a long time what does the body need to replace
Sugar, mineral ions, water
What are sports drinks
Solutions of sugar and mineral ions
What is water from sports drinks useful for in cells
Rehydrate
What is osmosis
The net movement of water from an area of high concentration to an area of low concentration
What does isotonic mean
Having the same concentration of a solution as another solution eg the drink docent ration matches the body fluids concentration
What is the benefit of having sports drinks
They help athletes to replace mineral ions and sugar as well as water
How are mineral ions lost from the body during exercise
In sweat
Large complex organisms have special ………… ………. To obtain all the food and oxygen they need
Exchange surfaces
What are soluble food materials or so lutes absorbed by
The intestine
What is absorbed and what is removed in the lungs
Oxygen is absorbed and co2 is removed
What 2 things do efficient exchange surfaces have
Large surface area, thin walls or short diffusion path
Efficient transport system, the blood supply in animals
What do the lungs contain for exchange
The gaseous exchange surfaces
What increases the surface area of the lungs
The alveoli
What do the alveoli have for efficient exchange
Thin walls, lathe surface area and good blood supply
How do the lungs maintain a steep concentration gradient
The are ventilated
What does oxygen disuse into which surround the alveoli
Many capillaries
What is the breathing system
The stems involved in breathing, the ribs, intercostal muscles,diaphragm as well as the lungs and the tubes which bring air into the body from outisde
Where are the lungs situated
The thorax, between the ribs and above the diaphragm, which separates the lungs from the abdomen
What is the benefit of having sports drinks
They help athletes to replace mineral ions and sugar as well as water
How are mineral ions lost from the body during exercise
In sweat
Large complex organisms have special ………… ………. To obtain all the food and oxygen they need
Exchange surfaces
What are soluble food materials or so lutes absorbed by
The intestine
What is absorbed and what is removed in the lungs
Oxygen is absorbed and co2 is removed
What 2 things do efficient exchange surfaces have
Large surface area, thin walls or short diffusion path
Efficient transport system, the blood supply in animals
What do the lungs contain for exchange
The gaseous exchange surfaces
What increases the surface area of the lungs
The alveoli
What do the alveoli have for efficient exchange
Thin walls, lathe surface area and good blood supply
How do the lungs maintain a steep concentration gradient
The are ventilated
What does oxygen disuse into which surround the alveoli
Many capillaries
What happen when we breath in
The intercostal muscles between the ribs and diaphragm contract
The rib cage moves up and out and the diaphragm flattens
The volume of the thorax increases
The pressure in the thorax decreases and air is drawn in
What happens when we breath out
The intercostal muscles of the rib cage and diaphragm relax
The rib age moves and in and the diaphragm becomes domed
The volume of the thorax decreases
The pressure increases and air is forced out
What is ventilation
The movement of air in and out of the lungs
Why may someone struggle to get enough oxygen into their bloodstream
If the alveoli are damaged, the surface area for gaseous exchange is reduced
If the tubes leading the lungs are narrowed, less air can be moved through them
If the person is paralysed, their muscles will not work to pull the rib age up and out
What was the iron lung used for
People with polio who are paralysed
How did the iron lung work
The person lay with their chest sealed in a large metal cylinder. When air was drawn out of the cylinder the persons chest moved out and they breathed in. The vacuum which was formed inside the cylinder created a negative pressure. When air was pumped back in to the cylinder it created pressure on the chest and forced air out of the persons lungs
What do breathing AIDS do
Force measured amounts of air into the lungs use positive pressure. Bags of air linked to masks can force air down the trachea
What is the advantage of positive pressure breathing AIDS compared to the iron Lung
It is smaller, easier to manage in the home and can be linked to computers for control
What happens to the food we eat
It is digested in the gut into small, soluble molecules
What happens to the dilutes in the small intestine
They are absorbed into the blood
What are the villi
They line inner surface of the small intestine and are the exchange surface for food molecules
What features do villi have to increase efficient exchange surfaces
They have thin walls and there are many capillaries close to the wall
They are finger like which greatly increase the surface area
How can the soluble products of digestion be absorbed into the villi
Either diffusion or active transport
What about the blood supply to the villi increase the efficiency of diffusion
Rich blood supply produces a step concentration gradient
Through what do gases diffuse in and out of cells in plants
Tiny holes called stomata
What is the size of stomata controlled by
Guard cells
What is oxygen used as in plants
It is needed for respiration and is a waste product of photosynthesis
What is co2 used for in plants
Photosynthesis and is a waste product of respiration.
What does the movement of gases in plants depend on
Which process, respiration or photosynthesis is happening quicker
Why do plants loose water through the stomata
Evaporation in the leaves p
Why are leaves flat and thin
So gases do not diffuse very far, there are also internal air spac
What do root hair cells increase the exchange of due to their large surface area
The absorption of water and mineral ions
How do the stomata prevent wilting
If the plant looses water faster than it is replaced the stomata close
Why is the waxy cuticle important
It is a waterproof layer which stops water loss
Why are the cells in plants not packed tightly
So they have a large surface area for gas exchange
What is the transpiration stream
The movement of water through the plant
What does water vapour diffuse through
Stomata
In what conditions is evaporation more rapid
In hot, dry, windy or bright conditions
How does wilting prevent water loss
The leaves collapse and hang down, reducing surface area
