Answer:
Organism in a lichen that provides protection - algae
Organism in a lichen that provides nutrients through photosynthesis - algae
Branched growth form of lichen - fruticose
Leafy growth form of lichen - foliose
Small and flat growth form of lichen - crustose
Explanation:
<em>Lichens are composite organisms that are formed from symbiotic relationships between fungi and cyanobacteria/algae. The Green algae layer offers food to the fungi by photosynthesis while the latter supplies nutrients and offers protection to the algal component. </em>
There are different types of lichen based on the growth structure:
Fruticose lichens grow upright and shrubby and posses either round or flat branches.
Foliose lichen appears like a leaf with upper and lower layers. They are usually flat or convoluted in nature.
Crustose lichens are small in appearance with flat, crusty growth on surfaces on which they grow.