A holdfast is a root-like structure that anchors aquatic sessile organisms, such as seaweed, other sessile algae, stalked crinoids, benthic cnidarians, and sponges, to the substrate.
Answer:
Photosynthesis a process used by plants and other organisms to convert light energy into chemical energy that, through cellular respiration, can later be released to fuel the organism's metabolic activities
they need sun water and CO2
Explanation:
You can easily remember it because the scientific name of leech is Hirudinaria. So it secretes anticoagulant named hirudin. Which help it to feed blood longer
