In some related species, sexual fusion is between larger and smaller motile cells, which may be called male and female; the female gametes may, as in the colonial genus Volvox, lose their flagella and become nonmotile, so becoming more like eggs.
Do algae have motile male gametes?
As angiosperms and gymnosperm have non motile male gamete while algae, bryo do have motile..
Which algae produce motile male gametes?
Option (3) Cladophora is the answer. Cladophora is an example of algae that produces motile homogametes. Male and female gametes have similar morphology. Volvox and Fucus are examples of oogamous reproduction, where the female gamete is large, non-motile and the male gamete is small, motile.
Are male gametes motile in plants?
In most eukaryotes, one or both sex gametes are motile, and gametes actively approach each other to fuse. However, in flowering plants, the gametes of both sexes lack motility. Two sperm cells (male gametes) that are contained in a pollen grain are recessively delivered via pollen tube elongation.
Does algae have motile sperm?
Any large, flat multicellular form is referred to as a thallus. Gametes that are identical are called isogametes; if different, heterogametes (oogamy refers to a large, non-motile egg; in such cases sperm are small and motile). About 4000 species of red algae are known. They inhabit the edges of the sea everywhere.
In which groups motile gametes are absent?
Red algae (Rhodophyceae) are characterized by the absence of any motile gametes or spores.
Is Cladophora Homogametic?
When the male and female gamete cannot be differentiated morphologically, the gametes are known as homogametes or isogametes. For example, Cladophora (an algae). When male and female gamete can be differentiated morphologically, such gametes are known as heterogametes.
Which male gamete is non-motile?
Non-motile sperm is an advanced character in Pinus.
Which plants produce motile male gametes?
Flagellated male gametes are present in Riccia,Dryopteris and Cycas. The male gametes of bryophytes are biflagellate, and those of pteridophytes are multiflagellate, except Selaginella having biflagellate gametes. The male gametes of gymnosperms are non motile except those of Cycas having multiciliate gametes.
Why are male gametes motile?
Unlike stationary (female) gametes, spherical, motile gametes designated as male could move both horizontally and vertically through the medium, without known means to explain their motility, because no flagella, amoeboid cell-shape changes or mucus trails were observed.
Can you conceive without motile sperm?
Similarly, rare non-motile sperm can appear in the ejaculate 1 or more years after vasectomy with no increased risk of failure (pregnancy or motile sperm). Therefore, repeat semen testing in men with rare non-motile sperm is unnecessary because pregnancy is very unlikely to occur in this setting.
What is the best sperm motility?
Semen analysis results table
|WHO reference range|
|Ejaculate volume||1.5–7.6 mL|
|Sperm concentration||15–259 million per mL|
|Total motility (progressive and non-progressive)||40–81 percent|
|Progressive motility||32–75 percent|