They get their shape from the cell wall
Green, unicellular algae, some of which resemble a microscopic banana shape is a desmid.
The theory of plants evolution that started from multicellular green algae is supported with evidence. First, the color and shape of small plants is similar with the green algae. Also, reproductive cycle , cell walls, the photosynthetic pigments are the same.
An amoeba is a cell that can alter its shape by extending and retracting pseudopods. The term describes a characteristic but does provide a place for it in the taxonomy of organisms. Organisms as diverse as protozoa, algae, animals, and fungi all have members that qualify as Amoebas. SOME algae are amoebas but most amoebas are NOT algae.
Pond silk is the common name of Spirogyra (algae) because it is very slimy in shape.
The shapes of protists include bells, stars, snowflakes ,and pincusions they range in size from microscopic algae to giant seaweeds.
Seaweeds are classified into three major groups; the green algae, the brown algae, and the red algae. Placement of seaweed into one of these groups is based on the pigments and colouration existing in the plant. Other seaweed features that are used to classify algae include: cell wall composition, reproductive characteristics, and the chemical nature of the photosynthetic products. Plant structure, form and shape are additional characteristics used to classify seaweed.
The only cells that have spiral shaped chloroplasts would be plant cells. This is because plants need chloroplasts to produce their own food.
Some of the types of algae are staghorn algae, black brush or beard algae, green spot algae, and green thread hair algae. Other types of algae are green water algae, and black green algae.
red algae, green algae, and brown algae
Diatoms are eukaryotic, they are a major class of algae and the most common type of phytoplankton. They are unicellular yet exist in colonies in the shape of ribbons.
plant+water=algae plant+ocean=algae plant+sea=algae