Habit and habitat: The member of the phylum porifera is commonly known as “Sponge’. Their distribution is worldwide i.e. they are found all over the world. Most of the species are marine. But some live in fresh water. Usually they live in colonies. General characteristics Simplest multicellular animal.Body wall with numerous pores. Through these pores … Read more
Learning Outcomes What is biodiversity Origin of biodiversity Nature of biodiversity Interrelationships of organisms How to measure biodiversity Biodiversity of Bangladesh Risks and remedies of biodiversity What is Biodiversity? The term biodiversity describes the great variety of life on Earth. Biodiversity refers to the variety of living things, including plants, animals, and microorganisms. We don’t … Read more
This section is to give you more information about science so you can know more about doing and understanding those things which make you ethical and prosperous. In the previous section, we saw that science is the word for human activity which produces being ethical and prosperous. This section is a more complete elaboration of … Read more
Ultrasound Images: about various ultrasound images for diagnostics. X-rays Modern medicine relies heavily on a variety of imaging techniques. They generate pictures of the interior of the human body for diagnostic purposes. The oldest of these imaging techniques is radiography. It generates pictures by irradiating the body with X-rays and recording the shadows of the internal … Read more
A sound wave is intense and loud if it has a large amplitude. However, the amplitude of a sound wave is hard to measure directly, and it is more convenient to reckon the intensity of a sound wave by the energy it carries. The intensity of a sound wave is defined as the energy per … Read more
The inner ear is a complex system of fluid-filled cavities in the temporal bone. Among these cavities are the three semicircular canals, whose function is not hearing, but rather the detection of movements of the head. The organ of the inner ear concerned with hearing is the cochlea, a tube of about 3.5 cm coiled … Read more
The middle ear is an air-filled cavity in the temporal bone of the skull. The cavity is connected to the nasopharynx by the Eustachian tube; this tube permits equalization of the air pressure in the middle ear with the external atmospheric pressure. The middle ear contains three small bones or oscines: the hammer, the anvil, … Read more
The ear performs the task of converting the mechanical oscillations of a sound wave into electric nerve impulses. Thus, it is similar to a microphone, which also converts the mechanical oscillations of sound into electric signals. However, the ear is unmatched in its ability to accommodate a wide range of intensities of sound. The human … Read more