Answer:
Water pollution may be defined as the contamination of the unwanted substance or pollutant with water that changes the normal characteristics of water. Three main contributors of ground water are as follows:
Chemical farming: The use of pesticides and fertilizers in the fields and its direct run off in river and groundwater causes the water pollution.
Industrial waste: The industrial waste consists of harmful chemicals and heavy metals. The direct discharge of chemical waste in the lakes, ground water and ponds makes the water dirty and causes water pollution.
Effluent from waste water treatment plant: The effluent and the harmful chemical waste release from the waste water treatment plant is the major contributor to the ground water. The effluents mix with the ground water and changes the ground water property.
Answer:
Hormones act as first messenger but not as second messengers.
Explanation:
Second messenger act as signaling molecule which are secreted in response to various biological signals generated by first messenger such as hormones,neurotransmitters etc.Second messengers include various bioactive molecules such as cyclic AMP(cAMP),cyclic GMP(cGMP),inositol triphosphate(IP3),diacylglycerol(DAG),calcium ions(Ca2+) etc.
Hormones are extracellular signaling molecules whereas second messengers are intracellular signaling molecules.
Once this initial energy is added, the wave travels through the medium until all its energy is transferred. In contrast, electromagnetic waves require no medium, but can still travel through one.
Answer:
Life cycle of a moss
Explanation:
LIFE CYCLE OF A MOSS FROM MATURED SPOROPHYTE STAGE
An embryo further develops into a pear-shaped sporangium, which is the *sporophyte stage of the plant*. The sporangium contains spore sacs, each of which is the spore mother cell that undergoes meiotic division to form four spores,The spores are released and germination
takes place giving rise to a protonema, which develops into a new gametophyte plant. The gametophyte generation or haploid phase of the moss is from the production of haploid spores after meiosis to the period just before fusion of the haploid antherizoid or haploid ovum. The sporophyte generation or diploid phase is from the diploid mother cells just before meiosis.
Examples of moss plants include Funaria hygrometrica, Polytrichum commune, Barbuda Indica.
