Mollusks: Classes, Characteristics, and Importance
There are three main classes of mollusks: Gastropoda, Bivalvia, and Cephalopoda.
Gastropoda
Gastropoda includes snails, slugs, and abalones. The name means “stomach foot.”
- Movement: They use their foot to slowly crawl.
Bivalvia
Bivalvia includes clams, oysters, scallops, and mussels. They have two shells.
- Movement: They are often sessile, anchored in place for filter feeding. Some can use their foot to dig through the sand.
Cephalopoda
Cephalopoda includes octopi, squid, and cuttlefish. The name means “
Read MoreCell Electric Potentials: Principles, Mechanisms, Applications
Electric Potentials Generated by Cells: Principles, Mechanisms, and Applications
The electric potentials generated by cells are fundamental to the functioning of the human body and all living organisms. These electrical signals govern many physiological processes, including nerve transmission, muscle contraction, and the function of the heart. Understanding the generation and function of electric potentials in cells is critical for comprehending how cells communicate with each other and how the body
Read MoreMale and Female Reproductive Systems: Anatomy
Male and Female Reproductive Systems
Spermatogenesis is responsible for producing sex cells called gametes. It reaches its maximum development at puberty, which occurs at different ages in boys and girls. Sexual dimorphism is different in both sexes. It is also responsible, along with the hormones, for producing the appearance of secondary sexual characteristics, such as the appearance of pubic hair, etc.
Male Reproductive System
The male reproductive system includes:
- Internal genital organs: These
Veins of the Human Body: Anatomy and Function
Azygos Vein
Azygos vein: It is formed in the thoracic cavity at the height of the 11th right intercostal space by the fusion of 2 medial and lateral branches. The lateral branch is formed by the union of the ascending lumbar vein and the right subcostal vein; the medial branch comes from the inferior vena cava or the right kidney vein. It empties into the posterior wall of the superior vena cava. Branches: It receives direct branches from the right posterior intercostal veins IV to XI (receiving
Read MoreInnate Immunity: Your Body’s First Line of Defense
Innate Immunity: Your Body’s Defense System
Your body produces a variety of white blood cells that defend against pathogens. A healthy immune system is always ready, providing innate immunity, which defends against all pathogens.
How Skin and Body Secretions Protect You
The skin is the first barrier against microorganisms. Body secretions like mucus, oil, sweat, tears, and saliva also play a crucial role. Mucus traps microorganisms in the respiratory and digestive tracts, which are then destroyed by
Read MoreLysosomes: Cell Digestion and Recycling Centers
Lysosomes: Cell Digestion and Recycling
Lysosomes are a set of structures whose function is to digest and lyse materials captured by the cell, including waste substances. These structures could be considered the digestive system of the cell. They are cytoplasmic vesicles, offering great polymorphism, surrounded by a unit membrane and a granular matrix that is dense and heterogeneous. Lysosomes act as digestive vacuoles and are present in all eukaryotic cells. The contents of the lysosome have an
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