Dissolved Substances Flashcards
Which 2 ways can dissolved substances move?
Diffusion
Active Transport
What’s osmosis?
The diffusion of water from a dilute to a more concentrated solution through a partially permeable membrane that allows the passage of water molecules, it’s a passive process (doesn’t require energy)
What causes water to move in and out of cells?
Differences in the concentrations of solutions inside and outside the cell
What do most soft drinks contain?
Water, sugar, ions
Why do sports drinks contain sugar?
To replace sugar used in energy release during activity
Why do sports drinks contain water and ions?
To replace water and ions lost during sweating
What 3 things do sports drinks contain?
Sugar
Water
Ions
What happens if ions or water are not replaced in the body?
The ion or water balance is disturbed and cells don’t work as efficiently
What’s active transport?
Substances being absorbed against a concentration gradient, requiring the use of energy from respiration
What does active transport enable?
Cells to absorb ions from dilute substances
Which 4 ways are many organ systems specialised for exchanging materials?
Large surface area, Being thin- short diffusion path, (animals) efficient blood supply, (animals, gas exchange) being ventilated
What are gas and solute exchange surfaces in humans and other organisms adapted to do?
Maximise effectiveness
What increases the difficulty of exchanging materials in organisms?
Their size and complexity
In humans, what increases the surface area of the lungs?
Alveoli
In humans, what increases the surface area of the small intestine?
Villi
