BIO 245 KLESATH EXAM 1 NCSU

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BIO 245 KLESATH EXAM 1 NCSU

UPDATED ACTUAL EXAM WITH

CORRECT SOLUTIONS.

• reflex mechanisms that stimulate hormone secretion - correct

answer- 1.Hormonal Stimulation: stimulus for release of

hormones by the binding of another hormone (eg the TSH from anterior pituitary binds to thyroid gland to release TH)

2.Humoral Stimulation: release of hormone in response to

change of blood nutrient levels (eg blood glucose levels rise so insulin is released from pancreas, or fall and glucagon is released)

3.Neural Stimulation: direct stimulation from nervous system to

endocrine gland (eg epinephrine and norepinephrine by adrenal medulla during fight or flight)

Hormonal Stimulation - correct answer- Stimulus for release of hormones by the binding of another hormone (eg the TSH from anterior pituitary binds to thyroid gland to release TH)

Humoral Stimulation - correct answer- release of hormone in response to change of blood nutrient levels (eg blood glucose levels rise so insulin is released from pancreas, or fall and glucagon is released)

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Neural Stimulation - correct answer- direct stimulation from nervous system to endocrine gland (eg epinephrine and norepinephrine by adrenal medulla during fight or flight)

Steroids - correct answer- lipid soluble molecules synthesized by cholesterol

• Gonads (Estrogen, Progesterone, Testosterone)
• Adrenal Cortex hormones (Corticosteroids like cortisol,

mineralocorticoids, aldosterone)

Biogenic Amines - correct answer- modified amino acids, water soluble (except thyroid)

• Catecholamines (epinephrine and norepinephrine)
• Thyroid Hormone → lipid soluble
• Melatonin

Proteins - correct answer- most hormones, small chains of amino acids, water soluble

• Small peptides and large polypeptides
• Glycoproteins

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Local Hormones - correct answer- DO NOT circulate in blood, so only affect either same cell that produced them (autocrine) or neighboring cells (Paracrine)

1. Eicosanoids: synthesized through enzymatic cascade,

Phospholipase A2 removes fatty acid from phospholipid within the plasma membrane --> prostaglandins

Prostaglandins - correct answer- -Famous eicosanoid

-are diverse group: synthesized by most tissues in the body

-Stimulate pain receptors, reduce fever, increase inflammatory response

Lipid soluble hormones: - correct answer- Can cross

membrane, but needs carrier protein while circulating in blood, once unbound they can enter the nucleus

• Has a longer half-life bc protected by carrier proteins
• Once inside the cells, hormone binds to intracellular receptor

either in nucleus of cytosol

• Once bound, forms a hormone receptor complex which

interacts with DNA directly in regions called Hormone Response Element (HRE)

• Initiates transcription/translation and production of a new

protein

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