Biology Test - 23

The intercalated disc is a unique feature of cardiac muscle, which is present in the region of the joining of two cardiac muscles. This intercalated disc help in the contraction of heart muscles in synchronization.On the other hand, the basement membrane and fibres are features of skeletal muscle, and Ligaments are the connective tissue that connects two bones at the joint.

Maltose in presence of maltase produces two molecules of glucose.

Lactose in presence of lactase produce glucose and galactose.

Sucrose in presence of sucrose produce glucose and fructose.

In Prophase stage the chromosomes first become visible.

Prophase is the first stage of mitosis. In prophase,

• Chromosomes condense and become visible.
• Spindle fibers emerge from the centrosomes.
• Nuclear envelope breaks down.
• Nucleolus disappears.

Nostoc is a blue-green algae with cells arranged in bead-like chains that are grouped together in a gelatinous mass. Ranging from microscopic to walnut-sized, masses of Nostoc may be found on soil and floating in quiet water. Reproduction is by fragmentation. A special thick-walled cell (akinete) has the ability to withstand desiccation for long periods of time.

Photosynthesis is the process, which is used by the plants to make their foods it generally involves water, sunlight, and Carbon dioxide in the process of making foods. By absorbing sunlight, water from the roots, and Carbon dioxide from the air, plants can perform the photosynthesis processes for making glucose and oxygen.

Spores are small reproductive cells that are used as agents of asexual reproduction. This germination produces the entire organism. Spores are produced by bacteria, fungi, algae, and plants.If the same type of spores is produced then it is called Homospory and if different types of spores are produced then it is called Heterospory.

Heterospory - When there is a production of different types of spores in a single plant, this condition is called heterospory. The structure, formation, and functions of these spores differ.

In pteridophytes, two different types of spores are present called Microspores and Megaspores.

Microspores are male spores that are smaller in size and larger in number. Microspores are produced in Microsporangium.

Megaspores are the female spores that are larger in size and smaller in number. Megaspores are produced in Megasporangium, these spores on germination produce the female gametophyte

Heterospory in pteriodophytes is shown by Selaginella, Isoetes, Marsilea, Salvinia, Azolla, Pilularia, etc.

Psilotum, Adiantum, and Pteris are Homosporous.

Vaccines produced through genetic engineering are safe as they contain antigen only from coat of pathogen.

Genetic engineering, also called genetic modification or genetic manipulation is the direct manipulation of an organism's genes using biotechnology. The vaccines produced through genetic engineering are considered as safe because the antigen is taken from the coat of pathogen. Conventional vaccines contain the whole unit of attenuated or killed pathogen.

Polyploidy is a condition in which the cells of an organism have more than two paired (homologous) sets of chromosomes. Most species whose cells have nuclei (eukaryotes) are diploid, meaning they have two sets of chromosomes—one set inherited from each parent. Polyploid is especially common in plants.

Momordica charantia having blood sugar lowering activity due toCharantin.

Momordica charantia L. (M. charantia), a member of the Cucurbitaceae family, is widely distributed in tropical and subtropical regions of the world. It has been used in folk medicine for the treatment of diabetes mellitus, and its fruit has been used as a vegetable for thousands of years.

Scavengers are the animals that feed on the dead and rotting organisms. Scavengers provide an important service to the ecosystem by removing disintegrating organisms and acting as an innate sanitation system. Scavengers assist conserve energy and nutrients received from rotting flesh within the top trophic levels and thus are capable of transferring the energy and nutrients further away from the source of the carrion.