The problem of dispersal through production of sporangia on the sporophyte
What would be the advantages of delaying rhodophyte meiosis? Initially, this provided a mechanism to increase spore production. In the normal zygote life cycle, only four spores are produced per fertilization event. By delaying meiosis, many more spores can be produced per mating. how ? If the zygote divides by meiosis, each diploid daughter cell can undergo meiosis to produce four haploid spores. The next step in the evolution of plant life was a system for dispersing spores on dry land.
Aquatic algae release spores into the water that can float and are dispersed by the movement of the water. To live on land, plants had to undergo two developmental changes—spore dispersal on land, and fertilization, or fusion of gametes, on land. The problem of dispersal was solved through the production of sporangia on the sporophyte. The sporangia ("spore cases") raise the spores above the ground so that they can be spread by the wind. Briefly, the sporophyte developed by delayed meiosis of the zygote. It is important to remember that the zygote remains in the maternal gametophyte archegonium.
The zygote divides by mitosis to produce an embryo, which remains attached to the gametophyte and depends on it for nutrition and survival. Initially, delayed meiosis provided a mechanism to increase the production of spores. 32 have expired. The distinction between protophloem and metaphloem and protoxylem and metaxylem is absent.
Phloem consists of sieve tubes, companion cells, phloem parenchyma and some phloem fibers. Sieve tubes carry part of the organic food. Associated cells control the functioning of the sieve tubes. Phloem parenchyma stores small amounts of organic matter. They operate it later as well.
Phloem fibers provide mechanical strength. Xylem is composed of vessels, tracheids, xylem parenchyma and xylem fibers. Tracheids and vessels are the tracheal elements. They also provide mechanical strength. Xylem fibers have only mechanical functions. Xylem parenchyma stores small amounts of food.
It also conducts juice later. Individual oversized scleroids and other cells occasionally occur. They are called idioblasts. Middle vein: The upper surface may show a small depression in the region of the middle vein and major veins while a ridge is present on the lower side. Mesophyll is absent. The epidermis is largely devoid of stomata.
The hypodermis can be towards both the upper and lower surface. It is collenchymatous or sclerenchymatous. It provides mechanical power. The MIDI region consists of either a single large vascular strand or multiple vascular bundles. There may be an outer boundary such as a bundle sheath or a pericycle.
An ideal teacher by acquiring knowledge of the secrets of conduct
Knowledge of psychology is useful in developing the teacher's relationship with children as well as with other children: Based on the knowledge of psychology, the teacher develops an intimate and elegant relationship with the child. Connects the bridge of affection with children. It provides the child with the malice of a father and the affection of a mother.
The study of psychology plays an important role in helping to develop relationships with children, as well as in establishing the association of other children with the way other children play in shaping a child's character.
The teacher develops group relationships by giving responsible tasks to the children. The psychology teacher is helpful in evaluating the student: the teacher's own knowledge as well as the student's success-failure can be obtained from the study of psychology. Teachers can also measure the personality-behavior of students through the study of psychology. He is aware of his greatness and limitations.
While teaching, he becomes aware of his strengths, limitations and shortcomings. Not only this, but teachers, being the step-brothers of children's motivation, try to be a perfect teacher and person by acquiring knowledge of the secrets of conduct. With the knowledge of psychology, the teacher tries to make the best use of his strengths by overcoming his shortcomings.
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