Seaweed has no seeds. Because the propagation mode of seaweed is asexual, and seaweed is a plant that lives in seawater, the climate on land is not suitable for it at all.

Although algae have no flowers, fruits, seeds and other structures to reproduce, they have various reproduction methods to adapt to the environment. In asexual reproduction, some cells can be directly divided into two parts, such as Spirogyra, which can be divided into several segments, and each segment will grow into an independent individual; Some algae can produce many flagellated spores,

You can swim freely, and each spore grows into a new individual when it matures; When the environment is bad, some algae can produce thick-walled resting spore, and when the environment is suitable, they will germinate and grow into new individuals. In sexual reproduction, some algae can produce female and male gametes and grow into new individuals after mating.

In the life of algae, asexual reproduction and sexual reproduction often alternate regularly, forming a complex life history. For example, laver and kelp, which we often eat, have different growth forms of sporophyte and gametophyte. Spore produces spores, and gametophyte produces female and male gametes, which is called "generation alternation".

Extended data:

Morphological characteristics of algae:

1. Big leaves: shriveled and curled, dark brown, partially frosted, 30 ~ 60 cm long. The trunk is cylindrical with conical protrusions, the main branches are born on both sides of the trunk, and the lateral branches are born in the axils of the main branches with short spines. The primary leaves are lanceolate or obovate, 5 ~ 7 cm long and 65438 0 cm wide, and the whole leaves are roughly serrated; The secondary leaves are strip-shaped or lanceolate, and there are branchlets with strip-shaped leaves between the axils.

Balloons are dark brown, spherical or ovoid, some with handles, the top is blunt and round, and some with thin and short tips. Crispy, soft when wet; Swelling after soaking, the meat is sticky. The smell is fishy and slightly salty.

2. Microalgae: small, 15 ~ 40 cm long. Branches alternate, without thorns. The leaves are strip-shaped or spoon-shaped, and the apex is slightly enlarged and hollow. Balloons are axillary, spindle-shaped or spherical with long handles. Hard quality.

growing environment

It grows in the shallow sea area below the low tide line-where the ocean meets the land, where the impact of waves is relatively mild, the seawater is rich in minerals and the sunshine is abundant. Both red algae and brown algae contain chlorophyll, although their colors are different.

You can use sunlight for photosynthesis to make food. They carry out photosynthesis, and the oxygen released is indispensable for animals to breathe. Seaweed plays an important role in making the marine world so colorful and lively.

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