Gas Exchange (Core). 6.4.1 Distinguish between ventilation, gas exchange and cell respiration.
Section 1 Exchange within the Environment. A cell must be able to take in energy and get rid of...
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Transcript of Section 1 Exchange within the Environment. A cell must be able to take in energy and get rid of...
Chapter 4Section 1
Exchange within the Environment
A cell must be able to take in energy and get rid of wastes
The exchange of materials between a cell and its environment takes place at the cell membrane
Exchange with the Environment
Movement of particles from an area of high concentration to low concentration
Naturally spreading out
Diffusion
Can occur across cell membranes or outside the cell
No energy is needed
Diffusion
Tea in cup of hot waterFragrance from a candle
Examples
Diffusion Demonstrations
The diffusion of water through the cell membrane
Pure water has the highest concentration (100%)
To lower concentration, something must be added to the water
Osmosis
Diffusion is anything, Osmosis is water
In diffusion or osmosis, particles move from areas of _High__ concentration to areas of _Low_ concentration.
Summarize the difference between diffusion and osmosis.
Salt water has a low concentration of water and high concentration of salt.
The cells of your body have high concentration of water and low salt.
Which way will the water move?
Thirsty for sea water?
Water from your cells will move from high to low concentration, leaving your cells and dehydrating you
Occurs through the proteins embedded throughout the membrane
No energy usedStill moving high to lowIncludes sugars and amino acids
Passive Transport
Occurs through the proteins embedded throughout the membrane
Uses energy (ATP)Occurs from LOW to HIGHExample – nutrients brought into the roots of a plant
Active Transport
Bringing large particles into the cell
Means “within the cell”The cell membrane surrounds a particle and encloses it in a vesicle
Endocytosis
Taking things out of the cellMeans “outside the cell”Vesicles are formed at the ER or Golgi and brought to the membrane to be released out of the cell
Exocytosis
Nearly all of the energy that fuels life comes from the sun
Cell Energy
The process by which plants capture light energy from the sun and convert it into sugar
6CO2 + 6H2O + light energy C6H12O6 + 6O2
Photosynthesis
Molecules in plant cells that absorb light energy
Chlorophyll is the main pigment for photosynthesis
Pigments
Cellular respirationFermentation
2 ways to release stored energy from food molecules
The process of releasing ATP in the cell from oxygen and glucose: producing carbon dioxide and water
Cellular respiration
The breakdown of sugars to make ATP in the absence of oxygen
Fermentation
Cellular respiration takes place in the mitochondria
C6H12O6 + 6O2
6CO2 + 6H2O + energy
Relates to breathing in that both use oxygen and release carbon dioxide
Like the lungs but not quite
In the muscles, producing lactic acid as a product
In bacteria and yeast, used in baking bread. The CO2 produced makes bread light and fluffy
2 types of fermentation