Endocrine & Excretory Systems - Flashcards

flashcards covering the key concepts from the Endocrine, Excretory, Eye & Ear, and Muscles sections of the notes.

Which gland secretes Growth Hormone (GH) and what is its primary function?

Anterior pituitary; stimulates growth.

Which anterior pituitary hormone stimulates the thyroid gland?

Thyroid-stimulating hormone (TSH).

Which anterior pituitary hormone stimulates the adrenal cortex to release corticosteroids?

Adrenocorticotropic hormone (ACTH).

Which hormone from the anterior pituitary stimulates the gonads to produce sperm and ova?

Follicle-stimulating hormone (FSH).

Which anterior pituitary hormone stimulates ovulation and testosterone production in gonads?

Luteinizing hormone (LH).

What is the function of prolactin (prolactin) from the anterior pituitary?

Stimulates milk secretion from the mammary glands.

Name the two hormones released by the posterior pituitary and their primary functions.

Oxytocin (stimulates uterine contractions); Antidiuretic hormone (ADH) promotes water retention by the kidneys.

What are the two thyroid-related hormones and their main actions?

Thyroxin (controls metabolic rate); Calcitonin (lowers blood calcium).

Which parathyroid hormone raises blood calcium levels?

Parathormone (PTH).

What is the role of the thymus?

Development of the immune system.

Which hormones are produced by the pancreas's islets of Langerhans and what are their roles?

Insulin lowers blood glucose; Glucagon raises blood glucose.

Name the hormones produced by the adrenal gland and their general roles (cortex vs medulla).

Adrenal cortex: Cortisone and Aldosterone; Adrenal medulla: Epinephrine (adrenaline) and Norepinephrine (noradrenaline).

Which hormones are produced by the testes and ovaries and what are their roles?

Testes: Testosterone (male sex hormone). Ovaries: Estrogen and Progesterone (female sex hormones; regulate secondary sex characteristics and prepare the uterus for pregnancy).

What roles does the pancreas play as an endocrine and exocrine gland?

Endocrine: insulin and glucagon regulate blood glucose; Exocrine: digestive enzymes secreted into the digestive tract.

What is the hypothalamus's role in the endocrine system?

It links the nervous and endocrine systems and regulates the pituitary; it releases releasing hormones that control the anterior pituitary.

Which hypothalamic releasing hormone stimulates the anterior pituitary to release TSH?

TRH (thyrotropin-releasing hormone).

What is the type of feedback that regulates T3/T4 levels via TRH and TSH?

Negative feedback loop.

Which hormone controls water reabsorption in the kidney and where is it released from?

Antidiuretic hormone (ADH); released from the posterior pituitary.

What are the four main nephron functions in order?

Filtration, Secretion, Reabsorption, Excretion.

During filtration, where does filtrate form and what does it contain?

From the glomerulus into Bowman's capsule; filtrate contains small molecules like glucose, salts, vitamins, and wastes such as urea.

What is the active process of moving substances into the nephron tubules called?

Secretion.

What happens during reabsorption in the nephron?

Most of the water and solutes (glucose, amino acids, vitamins) are transported back into the capillaries.

Which organ is the site of deamination and urea production and does not excrete substances from the body?

Liver.

What is the function of the urinary bladder?

Stores urine.

What are cones in the retina responsible for?

Color vision (color-distinguishing photoreceptors).

Name the eye structures that protect and refract light and control light entry (cornea, iris, lens, pupil) and their functions.

Cornea protects and allows light in; Iris controls light entry; Lens focuses light onto the retina; Pupil is the opening regulated by the iris.

What is the function of the ear canal, Eustachian tube, semicircular canals, and tympanum?

Ear canal carries sound; Eustachian tube equilibrates pressure; Semicircular canals help balance; Tympanum vibrates in response to sound.

What are the three types of muscle in humans and a key trait of each?

Smooth (involuntary; found in vessels/tracts); Skeletal (voluntary; multinucleate; works in pairs); Cardiac (involuntary; has its own rhythm).

What are myofibrils and what proteins do they contain that interact to cause contraction?

Myofibrils are composed of actin (thin) and myosin (thick) filaments; contraction requires actin–myosin interaction within sarcomeres, Ca2+ binding to troponin, and ATP.

What type of joint allows movement in all directions and can be found in the shoulder and hip?

Ball-and-socket joints.

Which gland distinguishes ligaments from tendons?

Ligaments connect bones to bones at joints; tendons connect bones to muscles.

What reflex would a percussion of the Achilles’ tendon elicit?

Extension of the leg (knee-jerk).

Which gland secretes the fight-or-flight hormone (epinephrine)?

Adrenal gland (adrenal medulla).

Which gland produces insulin?

Pancreas (islets of Langerhans).

Which gland produces iodine-containing hormones that affect metabolic rate, and what is one of those hormones?

Thyroid gland; Thyroxin (T4) or T3.

Which hormone lowers blood calcium levels?

Calcitonin.

Which gland secretes estrogen and progesterone in females?

Ovaries.

Which gland secretes Growth Hormone (GH) and what is its primary function?

Anterior pituitary; stimulates growth.

Which anterior pituitary hormone stimulates the thyroid gland?

Thyroid-stimulating hormone (TSH).

Which anterior pituitary hormone stimulates the adrenal cortex to release corticosteroids?

Adrenocorticotropic hormone (ACTH).

Which hormone from the anterior pituitary stimulates the gonads to produce sperm and ova?

Follicle-stimulating hormone (FSH).

Which anterior pituitary hormone stimulates ovulation and testosterone production in gonads?

Luteinizing hormone (LH).

What is the function of prolactin (prolactin) from the anterior pituitary?

Stimulates milk secretion from the mammary glands.

Name the two hormones released by the posterior pituitary and their primary functions?

Oxytocin (stimulates uterine contractions); Antidiuretic hormone (ADH) promotes water retention by the kidneys.

What are the two thyroid-related hormones and their main actions?

Thyroxin (controls metabolic rate); Calcitonin (lowers blood calcium).

Which parathyroid hormone raises blood calcium levels?

Parathormone (PTH).

What is the role of the thymus?

Development of the immune system.

Which hormones are produced by the pancreas's islets of Langerhans and what are their roles?

Insulin lowers blood glucose; Glucagon raises blood glucose.

Name the hormones produced by the adrenal gland and their general roles (cortex vs medulla).

Adrenal cortex: Cortisone and Aldosterone; Adrenal medulla: Epinephrine (adrenaline) and Norepinephrine (noradrenaline).

Which hormones are produced by the testes and ovaries and what are their roles?

Testes: Testosterone (male sex hormone). Ovaries: Estrogen and Progesterone (female sex hormones; regulate secondary sex characteristics and prepare the uterus for pregnancy).

What roles does the pancreas play as an endocrine and exocrine gland?

Endocrine: insulin and glucagon regulate blood glucose; Exocrine: digestive enzymes secreted into the digestive tract.

What is the hypothalamus's role in the endocrine system?

It links the nervous and endocrine systems and regulates the pituitary; it releases releasing hormones that control the anterior pituitary.

Which hypothalamic releasing hormone stimulates the anterior pituitary to release TSH?

TRH (thyrotropin-releasing hormone).

What is the type of feedback that regulates T3/T4 levels via TRH and TSH?

Negative feedback loop.

Which hormone controls water reabsorption in the kidney and where is it released from?

Antidiuretic hormone (ADH); released from the posterior pituitary.

What are the four main nephron functions in order?

Filtration, Secretion, Reabsorption, Excretion.

During filtration, where does filtrate form and what does it contain?

From the glomerulus into Bowman's capsule; filtrate contains small molecules like glucose, salts, vitamins, and wastes such as urea.

What is the active process of moving substances into the nephron tubules called?

Secretion.

What happens during reabsorption in the nephron?

Most of the water and solutes (glucose, amino acids, vitamins) are transported back into the capillaries.

Which organ is the site of deamination and urea production and does not excrete substances from the body?

Liver.

What is the function of the urinary bladder?

Stores urine.

What are cones in the retina responsible for?

Color vision (color-distinguishing photoreceptors).

Name the eye structures that protect and refract light and control light entry (cornea, iris, lens, pupil) and their functions.

Cornea protects and allows light in; Iris controls light entry; Lens focuses light onto the retina; Pupil is the opening regulated by the iris.

What is the function of the ear canal, Eustachian tube, semicircular canals, and tympanum?

Ear canal carries sound; Eustachian tube equilibrates pressure; Semicircular canals help balance; Tympanum vibrates in response to sound.

What are the three types of muscle in humans and a key trait of each?

Smooth (involuntary; found in vessels/tracts); Skeletal (voluntary; multinucleate; works in pairs); Cardiac (involuntary; has its own rhythm).

What are myofibrils and what proteins do they contain that interact to cause contraction?

Myofibrils are composed of actin (thin) and myosin (thick) filaments; contraction requires actin–myosin interaction within sarcomeres, Ca^{2+} binding to troponin, and ATP.

What type of joint allows movement in all directions and can be found in the shoulder and hip?

Ball-and-socket joints.

Which gland distinguishes ligaments from tendons?

Ligaments connect bones to bones at joints; tendons connect bones to muscles.

What reflex would a percussion of the Achilles’ tendon elicit?

Extension of the leg (knee-jerk).

Which gland secretes the fight-or-flight hormone (epinephrine)?

Adrenal gland (adrenal medulla).

Which gland produces insulin?

Pancreas (islets of Langerhans).

Which gland produces iodine-containing hormones that affect metabolic rate, and what is one of those hormones?

Thyroid gland; Thyroxin (T4) or T3.

Which hormone lowers blood calcium levels?

Calcitonin.

Which gland secretes estrogen and progesterone in females?

Ovaries.

What is the basic contractile unit of a muscle fiber?

Sarcomere.

What is the primary energy source directly utilized for muscle contraction?

ATP (Adenosine triphosphate).

Which ion is essential for initiating muscle contraction by binding to troponin?

Ca^{2+} (Calcium ions).

What protein makes up the thin filaments in a sarcomere?

Actin.

What protein makes up the thick filaments in a sarcomere?

Myosin.

Which part of the retina is responsible for sharp central vision and contains a high concentration of cones?

Fovea.

What structure transmits visual information from the retina to the brain?

Optic nerve.

What is the area of the retina where the optic nerve leaves the eye, resulting in no photoreceptors?

Blind spot (optic disc).

What process allows the eye to change its focus between objects at different distances?

Accommodation (changing the shape of the lens).

Which spiral-shaped structure in the inner ear is responsible for hearing?

Cochlea.

What are the three small bones in the middle ear called collectively, and what is their function?

Ossicles (malleus, incus, stapes); they transmit vibrations from the tympanum to the oval window.

What structure helps collect sound waves and channel them into the ear canal?

Pinna (outer ear).

Which part of the ear contains the organs for balance (semicircular canals and vestibule)?

Inner ear.

Which part of the nephron is primarily responsible for establishing a concentration gradient in the renal medulla, enabling water reabsorption?

Loop of Henle.

Which hormone causes the collecting duct to become more permeable to water, leading to increased water reabsorption?

Antidiuretic hormone (ADH) or vasopressin.

What is the tube that carries urine from the kidney to the urinary bladder?

Ureter.

What is the final tube through which urine leaves the body?

Urethra.

What is the process by which nitrogenous wastes are removed from amino acids in the liver?

Deamination.