Erectile tissue is tissue in the body with numerous vascular spaces, or

cavernous tissue Cavernous tissue refers to blood-filled spaces lined by endothelium and surrounded by smooth muscle. It is present in the erectile tissue of the penis and clitoris In amniotes, the clitoris ( or ; : clitorises or clitorides) is a female se ...

, that may become engorged with

blood Blood is a body fluid in the circulatory system of humans and other vertebrates that delivers necessary substances such as nutrients and oxygen to the cells, and transports metabolic waste products away from those same cells. Blood is com ...

. However, tissue that is devoid of or otherwise lacking erectile tissue (such as the

labia minora The labia minora (Latin for 'smaller lips', : labium minus), also known as the inner labia, inner lips, or nymphae, are two flaps of skin that are part of the primate vulva, extending outwards from the inner Vagina#Vaginal opening and hymen, vagi ...

, vestibule,

vagina In mammals and other animals, the vagina (: vaginas or vaginae) is the elastic, muscular sex organ, reproductive organ of the female genital tract. In humans, it extends from the vulval vestibule to the cervix (neck of the uterus). The #Vag ...

and

urethra The urethra (: urethras or urethrae) is the tube that connects the urinary bladder to the urinary meatus, through which Placentalia, placental mammals Urination, urinate and Ejaculation, ejaculate. The external urethral sphincter is a striated ...

) may also be described as engorging with blood, often with regard to

sexual arousal Sexual arousal (also known as sexual excitement) describes the Physiology, physiological and psychological responses in preparation for sexual intercourse or when exposed to Sexual stimulation, sexual stimuli. A number of physiological response ...

In sex organs

Erectile tissue exists in external genitals such as the corpora cavernosa of the

penis A penis (; : penises or penes) is a sex organ through which male and hermaphrodite animals expel semen during copulation (zoology), copulation, and through which male placental mammals and marsupials also Urination, urinate. The term ''pen ...

and their

homologs Homologous chromosomes or homologs are a set of one maternal and one paternal chromosome that pair up with each other inside a cell during meiosis. Homologs have the same genes in the same loci, where they provide points along each chromosome th ...

in the

clitoris In amniotes, the clitoris ( or ; : clitorises or clitorides) is a female sex organ. In humans, it is the vulva's most erogenous zone, erogenous area and generally the primary anatomical source of female Human sexuality, sexual pleasure. Th ...

, also called the corpora cavernosa. During penile or

clitoral erection Clitoral erection (also known as clitoral tumescence or female erection) is a physiological phenomenon where the clitoris becomes enlarged and firm. Clitoral erection is the result of a complex interaction of psychological, neural, vascular ...

, the corpora cavernosa will become engorged with arterial blood, a process called ''

tumescence Tumescence is the quality or state of being tumescent or swollen. Tumescence usually refers to the normal engorgement with blood ( vascular congestion) of the erectile tissues, marking sexual excitation, and possible readiness for sexual activity. ...

''.Chapter 35 in: This may result from any of various physiological stimuli which can be internal or external. This process of stimulation, due to internal or external stimuli, is also known as

. The

corpus spongiosum The corpus spongiosum is the mass of spongy tissue surrounding the male urethra within the penis. It is also called the corpus cavernosum urethrae in older texts. Structure The proximal part of the corpus spongiosum is expanded to form the ...

is a single tubular structure located just below the corpora cavernosa in males. This may also become slightly engorged with blood, but less so than the corpora cavernosa.

In the nose

Erectile tissue is present in the anterior part of the

nasal septum The nasal septum () separates the left and right airways of the Human nose, nasal cavity, dividing the two nostrils. It is Depression (kinesiology), depressed by the depressor septi nasi muscle. Structure The fleshy external end of the nasal s ...

and is attached to the turbinates of the nose. The

nasal cycle The nasal cycle is the subconscious alternating partial Nasal congestion, congestion and decongestion of the nasal cavity, nasal cavities in humans and other animals. This results in greater airflow through one nostril with periodic alternation ...

occurs as the erectile tissue on one side of the nose congests and the other side decongests. This process is controlled by the autonomic nervous system with parasympathetic dominance being associated with congestion and sympathetic with decongestion. The time of one cycle may vary greatly between individuals, with Kahana-Zweig et al. finding a range between 15 minutes and 10.35 hours though the average was noted as 2.15 ± 1.84 hours.

Other types

Erectile tissue is also found in the

urethral sponge The urethral sponge is a spongy cushion of biological tissue, tissue, found in the lower genitals, genital area of females, that sits against both the pubic bone and vaginal wall, and surrounds the urethra. Functions The urethral sponge is com ...

and perineal sponge. The

erection of nipples The nipple is a raised region of tissue on the surface of the breast from which, in lactating females, milk from the mammary gland leaves the body through the lactiferous ducts to nurse an infant. The milk can flow through the nipple passively, ...

is not due to erectile tissue, but rather due to the contraction of

smooth muscle Smooth muscle is one of the three major types of vertebrate muscle tissue, the others being skeletal and cardiac muscle. It can also be found in invertebrates and is controlled by the autonomic nervous system. It is non- striated, so-called bec ...

under the control of the

autonomic nervous system The autonomic nervous system (ANS), sometimes called the visceral nervous system and formerly the vegetative nervous system, is a division of the nervous system that operates viscera, internal organs, smooth muscle and glands. The autonomic nervo ...

References

Sexual anatomy {{Anatomy-stub ru:Пещеристое тело