The half of the total carbon dioxide fixation on earth is carried out by algae through
Being photosynthetic they increase the level of dissolved oxygen in their immediate environment.
A plant producing seeds but lacking flowers is
Gymnosperms are plants with produce seeds but lacks flower. These are non flowering plants. They produce naked seeds.
Identify the plant shown in the figure given below.
The plant shown above is cycas. This plant belongs to division cycadophyta and family cycadceae. It is diecious and native to India.
Which plant division is known as amphibians
Bryophytes are called as amphibians of plant kingdom as bryophytes can grow in both land andwater. Water is essential for completion of life cycle. So, they are called amphibians of plant kingdom.
All seed bearing plant, alternation of generation is
All seed-bearing plants i.e.,gymnosperms and angiosperms follow diplontic alternation of generation.
In Ulothrix or Spirogyra, reduction division (meiosis) occurs at the time of
Plant body of Ulothrix and Spirogyra, is gametophytic (haploid), they produce zoogametes (n) which fuses to form zygosporic (2n) diploid, which is a resting spore. Onset of favourable condition zygospore undergoes reductional division, or meiosis to produce zoo- meiospores
A moss plant are used as a fuel are
Species of Sphagnum, a moss, provide peat that has long been used as fuel.
Male and female gametophytes do not have free independent existence in
Unlike bryophytes and pteridophytes, in gymnosperms the male and the female gametophytes do not have an independent free-living existence.
The yellow or brown spots which have sporangia in fern are called
The yellow or brown spots which have sporangia in fern are called sori. Spores are produced inside these sporangia to start gamotophytic haploid life.
Megasporangium of seed plants are called
Megasporangium of seed plants are called ovule. Ovule is present inside the ovary which terminates into seeds on ripening. It represent female reproductive unit.
The cell wall of green algae is made up of
Green algae usually have a rigid cell wall made of cellulose.
Which plant division is known as amphibians of the plant kingdom?
Bryophytes are also called amphibians of the plant kingdom because these plants can live in soil but are dependent on water for sexual reproduction.
The structure formed by germinated fern spore is
Fern spore germinate to form a leafy structure called prothallus. On prothallus, male and female gametophyte germinate and produce respective germ cells.
In gymnosperms cross pollination is accompanied by
In Gymnosperms, cross pollination is mainly accompanied by wind. The pollen grains are produced in large quantity and generally lighter.
Angiosperm: roots :: Rhodophyta :?
Angiospermic plants have roots to hold the soil and remain erect. Similarly Rhodophytes have holdfast by which they remain attached with substratum to absorb water and minerals.
Which classes of algae possess chlorophyll a, chlorophyll c, carotenoids and xanthophylls?
Phaeophyceae possess chlorophyll a, c, carotenoids and xanthophylls. They vary in colour from olive green to various shades of brown depending upon the amount of the xanthophyll pigment
Bryophytes flourish is moist and shady environments because
These plants can live in soil but are dependent on water for sexual reproduction. They usually occur in damp, humid and shaded localities.
The megasporangium of naked seed plants are called
The cones bearing megasporophylls with ovules or megasporangiaare calledmacrosporangiate or femalestrobili.
Greatest extent of adaptation to various environments is found in
Adaptation is essential for survival of organism. The greatest extent of adaption in various environmental conditions is found in Angiosperms. Angiosperms are found in all kind of environment and altitudes.
Primary endosperm nucleus is formed by
Fusion of two polar nuclei with one male gamete is called triple fusion. Primary endosperm nucleus is formed by this product of triple fusion that divide mitotically to form endosperm.
The process of fusion between one large and non-motile female gamete with smaller, motile male gamete is termed as
Fusion between one large, non-motile (static) female gamete and a smaller, motile male gamete is termed as oogamous.
Archegoniophore occurs in
Archegoniophore occurs in Marchantia that develop on the thallus of Marchantia plant. Archegoniophoreproducegametes for alternation of generation.
The cone of Gymnosperms represent the
In gymnosperms, male and female cones are formed that produce male and female gametes. So, cone of gymnosperms represents thereproductive organs.
Primary endosperm nucleus is formed by
The pollen tubes enter the embryo-sac where two male gametes are discharged. One of the male gametes fuses with the egg cell to form a zygote (syngamy). The other male gamete fuses with the diploid secondary nucleus to produce the triploid primary endosperm nucleus (PEN).
Phloem of angiosperms differ from that of other vascular plants by the presence of
Phloem of angiosperms contain companion cells but other vascular plants lacks companioncells in their phloem cells. Phloem transport food form leaves to all other parts of plants.