types:
pore
any small opening in the skin or outer surface of an animal
canaliculus
a small canal or duct as in some bones and parts of plants
sinus,
venous sinus
a wide channel containing blood; does not have the coating of an ordinary blood vessel
nasolacrimal duct
a duct that carries tears from the lacrimal sac to the nasal cavity
Haversian canal
any of the many tiny canals that contain blood vessels and connective tissue and that form a network in bone
canalis inguinalis,
inguinal canal
oblique passage through the lower abdominal wall; in males it is the passage through which the testes descend into the scrotum and it contains the spermatic cord; in females it transmits the round ligament of the uterus
salivary duct
a duct through which saliva passes from the salivary gland into the mouth
ureter
either of a pair of thick-walled tubes that carry urine from the kidney to the urinary bladder
urethra
duct through which urine is discharged in most mammals and which serves as the male genital duct
vagina
the lower part of the female reproductive tract; a moist canal in female mammals extending from the labia minora to the uterus
epididymis
a convoluted tubule in each testis; carries sperm to vas deferens
ejaculatory duct
a part of the seminal duct formed by the duct from the seminal vesicle and the vas deferens; passes through the prostate gland
bronchiole
any of the smallest bronchial ducts; ending in alveoli
sweat duct
a small duct that conveys sweat from a sudoriferous gland to the surface of the skin
lacteal
any of the lymphatic vessels that convey chyle from the small intestine to the thoracic duct
trachea,
windpipe
membranous tube with cartilaginous rings that conveys inhaled air from the larynx to the bronchi
enteron
the alimentary canal (especially of an embryo or a coelenterate)
ostiole
a small pore especially one in the reproductive bodies of certain algae and fungi through which spores pass