Anatomy: Urinary and Reproductive Systems

Urinary system function

Regulate volume and chemical composition of blood
Dispose of waste in urine- the major organs of secretion

Urinary system components

Kidney
Ureter
Urinary bladder
Urethra

Kidney anatomy

Cortex= superficial region; light
Medulla= deeper region; dark
Consists of renal pyramids

Kidney basic structure

Nephron- starts and ends in cortex; loop descends into medulla and back to cortex
To collecting duct- runs through cortex and medulla
Out of kidney

Kidney Function

Filtration- blood plasma passively squeezed into nephron, becomes filtrate
Reabsorption- move molecules back to blood (mostly actively)
Secretion- actively pump molecules into filtrate
Resulting fluid= urine

Renal corpuscle

Glomerulus= fenestrated capillaries
Glomerular capsule- podocytes
Glomerulus+ glomerular capsule= a “sieve” for filtration
-proteins and cells do not pass through
-Filtrate= water and other small molecules

Proximal convoluted tubule

resorption and secretion
Simple cuboidal epithelium

Loop of henle (nephron loop)

Thin segment- reabsorbs water (passive diffusion); simple squamous epithelium
Thick segment- reabsorbs salt; simple cuboidal epithelium

Distal convoluted tube

Resorption and secretion
Simple cuboidal epithelium

Collecting duct

Resorption and secretion
Simple cuboidal epithelium

Embryonic and fetal development

Development of homologous structures in male and female external genitalia
Genital tubercle- penis/ clitoris
Urethral folds- penile urethra/ labia minora
Labioscrotal swellings- scrotum/ labia majora

Male anatomy

Testis- produces sperm
Epididymis- sperm maturation and storage
Ductus deferens- delivers stored sperm by peristalsis
Seminal vesicle (gland)- produces majority of semen

Male anatomy continued

Ejaculatory duct- combines sperm with semen, empties into urethra
Prostate (gland)- contributes to semen
Bulbourethral glands- produce pre-ejaculatory fluid
Penis- erectile organ, contains most of urethra, elimination of urine, and ejaculation of semen

Female anatomy

Ovary- releases oocyte during ovulation
Uterine tube- transports oocyte to uterus
-has fimbriae (finger-like projections) to pull oocyte in
-ciliated simple columnar epithelium
-site where fertilization usually occurs
Uterus (womb)- site of embryonic/ fetal development

Female anatomy continued

Vagina- passageway for sexual intercourse and giving birth
Two pairs of folds at vaginal orifice- labia majora (outer fold) and labia minora (inner folds)
Greater vestibular glands- secrete lubricant
Clitoris- erectile organ