Search results
Results From The WOW.Com Content Network
Spores form a part of the life cycles of a diverse range of organisms such as many bacteria, plants, algae, fungi and some protozoa. In Saccharomyces cerevisiae (Kingdom Fungi), the set of early genes activating sporulation is induced by Ime1 (Inducer of Meiosis 1) and a regulator of middle genes is Ndt80p. [4]
Bacteria produce a single endospore internally. The spore is sometimes surrounded by a thin covering known as the exosporium, which overlies the spore coat. The spore coat, which acts like a sieve that excludes large toxic molecules like lysozyme, is resistant to many toxic molecules and may also contain enzymes that are involved in germination.
Bacterial spores are not part of a sexual cycle, but are resistant structures used for survival under unfavourable conditions. [4] Myxozoan spores release amoeboid infectious germs ("amoebulae") into their hosts for parasitic infection, but also reproduce within the hosts through the pairing of two nuclei within the plasmodium, which develops ...
Plant spores are most obvious in the reproduction of ferns and mosses. However, they also exist in flowering plants where they develop hidden inside the flower. For example, the pollen grains of flowering plants develop out of microspores produced in the anthers. Reproductive spores grow into multicellular haploid individuals or sporelings.
Myxococcus is a genus of bacteria in the family Myxococcaceae. Myxococci are Gram-negative, spore-forming, chemoorganotrophic, obligate aerobes. They are elongated rods with rounded or tapered ends, and they are nonflagellated. The cells utilize gliding motility to move and can predate other bacteria. The genus has been isolated from soil.
Flowering plants contain microsporangia in the anthers of stamens (typically four microsporangia per anther) and megasporangia inside ovules inside ovaries. In all seed plants, spores are produced by meiosis and develop into gametophytes while still inside the sporangium. The microspores become microgametophytes (pollen).
The stages of germination of a pea plant: A. seed coat, B. radicle, C. primary root, D. secondary root, E. cotyledon, F. plumule, G. leaf, H. tap root. The part of the plant that first emerges from the seed is the embryonic root, termed the radicle or primary root. It allows the seedling to become anchored in the ground and start absorbing water.
A 2009 study compared the density of spores found in soil (about 10 6 spores per gram) to that found in human feces (about 10 4 spores per gram). The number of spores found in the human gut was too high to be attributed solely to consumption through food contamination. [15] In some bee habitats, B. subtilis appears in the gut flora of honey ...