Human Reproductive System and Nervous System Functions

Male Reproductive System

• Glands: The seminal vesicles and prostate gland produce substances that are dumped into the vas deferens. These secretions, along with sperm, constitute semen.
• Genital Tracts:
  • Epididymis: A folded tube where spermatozoa are stored.
  • Vas deferens: Tubes leading sperm from the epididymis to the urethra.
  • Urethra: The evacuation duct of the bladder where the vas deferens also flows.
• Penis: A cylindrical cone with an enlarged tip called the glans, covered by a fold of skin called the foreskin.
• Testes: Two organs contained in a bag called the scrotum. They produce sperm and testosterone.

Stages of Labor

• Dilation Phase: Spontaneous contractions of the uterine wall begin. These contractions push the child toward the exit of the uterus, which causes dilation of the cervix. The pressure causes the rupture of the amniotic sac.
• Expulsion Phase: Contractions become increasingly long and intense, pushing the fetus to the exterior. The mother can help the baby leave by voluntarily contracting the abdominal muscles.
• Delivery Phase: Contractions resume, causing the placenta to detach from the uterine lining, leading to its expulsion. The broken blood vessels cause bleeding that ceases with the retraction of the uterus.

Voluntary and Involuntary Acts

Voluntary Acts

Voluntary acts are controlled by the cerebral cortex. They are conscious movements.

Stimulus - Sensory organ - Sensory nerve - Brain - Motor nerve - Muscle or gland

Involuntary Acts

Involuntary acts are controlled by the spinal cord, such as blinking, a thump, or a burn.

Reflex Arc: This is done through a structure called the reflex arc.

• Sensory neuron: Tactile corpuscles form a set of sensory axons.
• Association neuron: The sensory neuron connects with the motor neuron, processing the appropriate response to the stimulus in the form of a nervous impulse.
• Motor neuron: Sends the response designed to flex muscles and eliminate the sensation of pain.

Hormonal Coordination System

Organs formed in specialized cells manufacture and secrete substances called endocrine glands, which make hormones that pour into the blood.

• Pituitary:
  • Growth hormone
  • Thyrotropin: Thyroid secretion
  • Adrenocorticotropin: Secretion of the adrenal glands
  • Gonadotropins: Regulate the activity of the sexual glands
  • Lactotroph: Milk secretion in women
• Thyroid: Thyroxine stimulates the chemical activity of the cell.
• Adrenal Glands:
  • Adrenaline stimulates heart rate and respiration.
  • Cortisone stimulates the synthesis of glucose and the destruction of fats.
• Pancreas:
  • Insulin stimulates processes that decrease blood glucose.
  • Glucagon increases the amount of blood glucose.
• Testicles: Testosterone regulates the function of male sexual organs.
• Ovaries: Progesterone and estradiol regulate the development and functions of female sexual organs and prepare the body for a possible pregnancy.