Test: Kingdom Protista- 2 - NEET MCQ

• Euglenoids have a protein rich layer called pellicle which makes their body flexible.
• Euglenoids have two flagella that help in their movement.
• Euglena changes its body shape during its movement and this phenomenon called as metaboly is possible due to pellicle.

• Slime moulds are considered to be fungus like protists since they grow in moulds and reproduce using spores.
• But there are many differences between Slime moulds and fungi.
• Unlike fungi, slime moulds lack chitin in their cell wall and are mobile.

Diatomaceous earth is primarily composed of silica embedded in the cell walls of diatoms. The indestructible nature of these walls, due to silica, leads to the accumulation of diatomaceous earth over billions of years.

Chrysophytes They have a cell wall made of two halves.

In Chrysophytes, cell walls are formed by the two things overlapping shells. This fit together in a small box. The walls are embedded with silica and thus walls are indestructible.

In diatoms call wall is arranged in the form of lid like soap bar. So it's cell wall has divided in two parts.

• Pseudopodia help amoeboids in both locomotion and ingestion of food.
• Pseudopodia are temporary extensions in amoeba that help them to move to as well as intake food by surrounding it with temporary extensions.

Diatoms are phytoplankton that floats on the water surface. They are the primary photosynthetic producers in marine food chains and store their food as lipids and polysaccharide leucosine. Since lipids have a lesser density than that of seawater, diatoms store oil or lipids in their vacuoles to maintain the buoyancy and thereby to float on water.

Cell of Diatoms are surrounded by cell wall having two parts or frustules; frustules make two overlapping halves (the epitheca and the hypotheca). Presence of numerous tiny pores in frustules connects the protoplast of the cell with the outside environment. The pectin substance of cell wall is richly impregnated with silica, which creates patterns of minute perforations and striations. Around 90 percent of diatomaceous cell wall is silica. Shells of diatoms are highly resistant to decomposition due to presence of silica and are deposited in ocean beds leading to formation of porous diatomaceous earth. It serves as porous acoustic material i.e. a solid material with cavities/channels to facilitate the entry of sound waves and their absorption with very little reflection. This makes option B correct. Dinoflagellates have armoured cellulosic cell wall while euglenoids lack cell wall but have pellicle which is a semi-rigid proteinaceous structure. Zooflagellates are protozoans that lack cell wall.

• Movement in paramecium is due to hair like structures called cilia that grows on its body.
• Paramoecium can move actively due to the presence of thousands of cilia.
• Cilia performs rhythmic movement in order to steer food containing water into the gullet.

Unicellular organisms fall into two general categories: prokaryotic organisms and eukaryotic organisms. Prokaryotes include bacteria and archaea. Many eukaryotes are multicellular, but the group includes the protozoa, unicellular algae, and unicellular fungi.