D
Low-pressure systems are associated with clouds and precipitation that minimize temperature changes throughout the day, whereas high-pressure systems normally associate with dry weather and mostly clear skies with larger diurnal temperature changes due to greater radiation at night and greater sunshine during the day.
Sponges are similar to other animals in that they are multicellular, heterotrophic, lack cell walls and produce sperm cells. Unlike other animals, they lack true tissues and organs, and have no body symmetry.
The shapes of their bodies are adapted for maximal efficiency of water
flow through the central cavity, where it deposits nutrients, and leaves
through a hole called the osculum. Many sponges have internal skeletons of spongin and/or spicules of calcium carbonate or silicon dioxide. All sponges are sessile
aquatic animals. Although there are freshwater species, the great
majority are marine (salt water) species, ranging from tidal zones to
depths exceeding 8,800 m (5.5 mi).
Answer:
Chromosomes contain genes, which help to determine an organism's traits. Genes come in alternate forms called alleles. The actual gene combination that an organism receives from its parents is called its genotype, while the trait that gets expressed as a result is referred to as its phenotype. If an offspring receives the same type of allele for a given gene from each parent, it is said to be h o m o z y g o u s. If the alleles differ, it is h e t e r o z y g o u s.
Explanation:
Answer:
B) cytoplasmic streaming in hyphae
Explanation:
Fungal mycelium refers to the branched vegetative structure of the fungi which is formed by the growth of the hyphae. The hyphae contain three zones of growth: the apical, subapical and zone of vacuolation.
The hyphae grow in the apical region which forms a branched structure in which the cytoplasm continuously moves between the hyphae at the point of fusion towards the growing tip. This movement of the cytoplasm towards the growing tip is known as "cytoplasmic streaming".
This streaming of cytoplasm is responsible for the formation of a zone of vacuolation and the mycelium is formed.
Thus, Option-B is the correct answer.
The growing tip eventually gives rise to a branch. This is the beginning of the branched mycelium. Growing tips that come in contact with neighbouring hyphae often fuse with them to form a hyphal net. In such a vigorously growing system, the cytoplasm is in constant motion, streaming toward the growing tips. Eventually, the older hyphae become highly vacuolated and may be stripped of most of their cytoplasm.
