What this topic covers
Organisms exchange substances with their environment has 4 subtopics:
- Surface area to volume ratio
- Gas exchange
- Digestion and absorption
- Mass transport
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AS Level AQA Biology · Topic 3 of 4
Organisms exchange substances with their environment – AS Level AQA Biology revision notes
Choose a subtopic. Organisms exchange substances with their environment covers Surface area to volume ratio, Gas exchange, Digestion and absorption, and Mass transport in AS Level AQA Biology. 13 lessons in 4 subtopics.
Revise Organisms exchange substances with their environment for AS Level AQA Biology, including Surface area to volume ratio. 13 lessons across 4 subtopics.
13
Lessons
4
Subtopics
Organisms exchange substances with their environment lessons by subtopic
13 lessons, grouped by subtopic.
Surface area to volume ratio
Gas exchange
Digestion and absorption
Mass transport
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Frequently asked questions
What is Organisms exchange substances with their environment?
Organisms exchange substances with their environment covers Surface area to volume ratio, Gas exchange, Digestion and absorption, and Mass transport in AS Level AQA Biology. 13 lessons in 4 subtopics.
What is COPD?
Chronic obstructive pulmonary disease (COPD) is an umbrella term covering chronic bronchitis and emphysema together. The Lung Disease and Risk Factors notes cover this in full.
What is gas exchange?
Gas exchange is the diffusion of oxygen from the air in the alveoli into the blood and of carbon dioxide from the blood into the alveoli. The The Human Gas Exchange System notes cover this in full.
Where do absorbed glucose and amino acids go?
Absorbed glucose and amino acids pass by facilitated diffusion into the blood capillaries of the villus, then enter the hepatic portal vein and travel to the liver. The Absorption in the Ileum notes cover this in full.
What is transpiration?
Transpiration is the evaporation of water from the surfaces of mesophyll cells inside the leaf and its diffusion out through open stomata as water vapour. The Xylem Transport: Cohesion-Tension Theory notes cover this in full.
What happens during the cardiac cycle?
The cardiac cycle has three phases. The The Cardiac Cycle & Cardiovascular Disease notes cover this in full.
What do the semilunar valves do?
The semilunar valves sit at the base of the pulmonary artery and aorta. The The Cardiac Cycle & Cardiovascular Disease notes cover this in full.
What is translocation in plants?
Translocation is the movement of organic substances, mainly sucrose and amino acids, through the phloem from sources to sinks. The Phloem Transport: Mass Flow Hypothesis notes cover this in full.
What is the structure of haemoglobin?
Haemoglobin is a globular protein with quaternary structure: four polypeptide subunits, two alpha and two beta chains in adult humans. The Haemoglobin and Oxygen Transport notes cover this in full.