Zoology

The anagen phase is the first stage of the hair life cycle. It is the prolonged phase of the hair growth cycle that lasts for months to years. Cells at the base of the follicle actively divide and multiply during this phase to build up a hair strand. Hair follicles are the hair-forming factories present […]

What are the layers of the hair shaft? The answer is there are three layers in the hair shaft; the medulla, cortex and cuticle. The medulla is the deepest layer of hair seen only in thick hairs. The cortex is the central layer of the hair shaft, giving strength, shine, colour and texture to your

The difference between polyp and medusa relies upon motility and shape. Members of the phylum Cnidaria have two different forms of individuals or zooids (polyp and medusa). Polyps are the sessile or fixed individuals, while medusae are motile or free-swimming zooids. Polyps appear more or less cylindrical, whereas medusae appear umbrella-shaped. Cnidarians can exist as

The structure of paramecium seems slipper-like. Paramecium comprises organelles common to eukaryotes. They contain specialized membrane-bound organelles and a well-defined nucleus. Besides that, they are unique in having contractile vacuoles, mouth pore and anal pore. Paramecium contains organelles necessary to sustain life, including growth, metabolism and reproduction. For the movement, they have small hair-like outgrowths

The difference between amoeba and paramecium relies on locomotion. Amoeba moves and feeds with pseudopods or temporary extensions. Activation of microfilament polymerization propels the cell membrane, ensuing pseudopodia formation. Paramecium moves through short hair-like cilia. Many tiny hair-like cilia are present throughout the pellicle. Its number varies from species to species. Oral cilia surround the

The anatomy of the rib cage in the human body contains twelve pairs of ribs, twelve thoracic vertebrae with one sternum and ten costal cartilages. It is a semi-solid bony and cartilaginous structure. The rib cage is also called the thoracic cage. It makes up the thorax or chest segment of our body, which exists

Euglena eyespot is also called stigma or eyespot apparatus. It generally has a bright red colour appearance. Euglena is a unicellular photosynthetic organism having an eyespot apparatus as a light-receptive organelle. The red colour of the eyespot in Euglena is due to the presence of carotenoid pigment granules. In addition, it contains photoreceptors, structural, metabolic

A pedigree analysis chart provides an important tool to study the inheritance of genes. It also gives precise information about the family members through diagrammatic representation. Sometimes, it is also known as the “family or genealogic tree“. A pedigree chart uses internationally accepted symbols, lines, numbers and letters To illustrate different individuals, their interrelationship, the

The difference between pectoral and pelvic girdle is mainly due to the following factors like the type of bones contributing to the formation, association of bones and articulations. Collar bone (clavicle) and the shoulder blade (scapula) are the two types of bones contributing to shoulder muscle or pectoral girdle formation. Hip or coxal bones solely

Human skin layers constitute the body’s outer covering that shields the internal cells, tissues, and organs against the changing environment, allergens, and pathogens. The human skin is the largest organ among the other components of the integumentary system. Besides its immunity role, skin regulates body temperature, synthesis of vitamin D, and sensation of touch, heat,