5.2 understand the effects on crop yield of increased carbon dioxide and increased temperature in glasshouses

Okay so, I mainly covered this, along with other factors, in point 5.1, but here it is again...

If carbon dioxide is increased, the rate of photosynthesis will be increased. Meaning more photosynthesis will occur each day, meaning a bigger crop yield.

If temperature is increased, plants can grow throughout the winter and don't die of frost etc. This also lowers the rate of transpiration (as there is a lower concentration gradient inside vs outside the plant leaf so the rate of transpiration is lower).