Related Concept Videos

Defense Mechanism Against Infection01:26

Defense Mechanism Against Infection

Natural flora, body system defenses, and inflammation are natural barriers of the body against infectious agents regardless of previous exposure. Normal floras of the human body refer to the microbial population that colonizes the skin and mucous membranes.
In addition, many body organ systems have unique defenses against infection. The skin is an intact, multilayered surface preventing invasion by microorganisms unless impaired. Mucous membranes lining the mouth, nose, and eyelids are barriers...
Surface Membrane Barriers01:18

Surface Membrane Barriers

The skin and mucous membranes serve as the primary line of defense against pathogens by providing both physical and chemical protection. These barriers are essential in preventing the entry and establishment of microbes, thereby maintaining the integrity of the host.
The outer layer of the skin, the epidermis, is a robust barrier comprising layers of closely packed keratinized cells. This dense arrangement prevents microbes from penetrating the body. The periodic shedding of epidermal cells...
External Female Genitals01:15

External Female Genitals

The vulva encompasses the external structures of the female reproductive system. At the forefront is the monpubis, a cushion of fatty tissue atop the pubic bone. Once puberty sets in, this area typically grows hair. Extending from just behind the mons pubis are the labia majora (labia = 'lips'; majora = 'larger'), which are larger skin fs olds coated with hair. Nestled within are the labia minora (labia = 'lips'; minora = 'smaller'), which are thinner, more pigmented, and hairless. While the...
Vagina01:26

Vagina

The vaginal canal is a tubular structure averaging about 10 cm in length that acts as the entryway to the female reproductive system and the passageway for menstrual flow and childbirth. The interior walls of the vagina exhibit concentric folds called rugae and are topped by an area known as the fornix, which connects with the protruding cervical portion of the uterus. This canal is comprised of an external fibrous layer, a muscular middle layer, and an inner lining with mucosal rugae, which...
Birth Control Methods01:22

Birth Control Methods

Vasectomy is a surgical form of male sterilization that involves severing and sealing the vasa deferentia, preventing sperm from mixing with semen during ejaculation. Because a vasectomy does not impact the testes' ability to produce testosterone, hormone levels, libido, and sexual function generally remain unchanged. While vasectomy is highly effective in preventing pregnancy, with a success rate near 99.85%, rare cases of recanalization (spontaneous reconnection) can occur. Although vasectomy...
Intrauterine Drug Delivery Systems01:21

Intrauterine Drug Delivery Systems

Controlled-release systems for intravaginal and intrauterine drug delivery have been developed primarily for the administration of contraceptive steroid hormones. These delivery routes circumvent first-pass hepatic metabolism, thereby enhancing bioavailability and allowing for reduced systemic dosages compared to oral administration. Such approaches contribute to improved therapeutic efficacy and patient compliance, particularly in long-term contraceptive regimens.Intravaginal Drug Delivery...