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The epithelial cells in the lungs are arranged into alveoli. Explain how the alveoli create a surface for efficient gaseous exchange.

Alveoli are made of two main types of cells. The alveoli walls are made of a single layer of squamous alveolar cells (aka Type I cells ), which are flat and thin, further shortening the diffusion distance. A...
YM
Answered by Yasamin M. • Biology tutor
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Glucose is filtered out of the blood, but is not found in urine. Explain why glucose is not present in urine

Glucose is filtered out of the blood in the glomerulus of the kidneys. All of the glucose is then is actively transported back into the capillaries in the area of the nephron called the proximal convoluted t...
AC
Answered by Alex C. • Biology tutor
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Describe how mRNA is produced in the nucleus of a cell

Production of mRNA is called Transcription, which can be divided into 3 stages: Initiation, Elongation and Termination.Initiation: DNA Helicase (Enzyme) binds to a promoter region of DNA (a short section of ...
GK
Answered by George K. • Biology tutor
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Describe and explain the effects of non-optimal pH and temperature on enzyme activity.

Enzymes at the wrong pH experience changes in the charge of the molecule, this can cause impacts on hydrogen and iconic bonds. Enzymes become denatured as terry structure is lost and the active site is no lo...
DW
Answered by Daisy W. • Biology tutor
6473 Views

How are the lungs adapted to increase the rate of diffusion? 3 Marks

Increase in surface area, which is provided by the many alveoli that are located at the end of the bronchioles. These can number in the thousands. The alveoli have a thin wall, one cell thick, so diffusion c...
LC
Answered by Louise C. • Biology tutor
6101 Views