In which group of animals is the coelom filled with blood?

Draw the diagram of $Spirogyra$ and label the following parts:
$(a)$ Cell wall $(b)$ Pyrenoid $(c)$ Nucleus $(d)$ Chloroplast.

Is the given figure of an angiosperm plant a dicot or a monocot? Differentiate between dicot and monocot plants on the basis of venation in the leaf and the number of cotyledons in the seed.

$A$ plant specimen was found without differentiated roots.
$(a)$ Which plant structure helps in attaching this plant to the substratum?
$(b)$ To which group would you classify this plant?
$(c)$ Which plant could it be?

Classify the following organisms based on the presence of a true coelom: $Spongilla$,$Planaria$,$Scorpion$,$Birds$,$Ascaris$,$Nereis$.

The book $Systema \text{ } Naturae$ was written by: