Endocrine System Hormone Functions

The video explains the endocrine system, focusing on how hormones are secreted by glands and travel through the bloodstream to target cells. It distinguishes between steroid and non-steroid hormones, detailing their mechanisms of action. Steroid hormones, being hydrophobic, require transport proteins to reach target cells, where they easily pass through cell membranes. Non-steroid hormones, hydrophilic in nature, cannot enter cells directly and instead use surface receptors to activate secondary messengers like cyclic AMP, which then influence cellular responses.

What is the primary function of the endocrine system?

• To transport oxygen in the blood

• To secrete hormones that regulate various body functions

• To digest food and absorb nutrients

• To protect the body from infections

How do hormones reach their target cells?

• Through the lymphatic system

• By direct contact with target cells

• Via the bloodstream

• Through nerve impulses

What characteristic allows steroid hormones to enter target cells easily?

• Their electrical charge

• Their hydrophilic nature

• Their small size

• Their hydrophobic nature

Which type of hormone requires a transport protein to travel in the bloodstream?

• Neither steroid nor non-steroid hormones

• Both steroid and non-steroid hormones

• Steroid hormones

• Non-steroid hormones

What is the main difference between steroid and non-steroid hormones in terms of solubility?

• Both are hydrophilic

• Both are hydrophobic

• Steroid hormones are hydrophilic, non-steroid hormones are hydrophobic

• Steroid hormones are hydrophobic, non-steroid hormones are hydrophilic

Why do non-steroid hormones require a secondary messenger?

• They are not recognized by the cell

• They are unstable in the bloodstream

• They are hydrophilic and cannot pass through the cell membrane

• They are too large to enter the cell

What is the primary messenger in the endocrine system?

• The secondary messenger

• The hormone

• The receptor

• The target cell

What is the role of a G protein in the action of non-steroid hormones?

• To bind directly to DNA

• To activate an enzyme on the cell membrane

• To degrade the hormone

• To transport hormones in the blood

What molecule is often used as a secondary messenger in non-steroid hormone action?

• ATP

• Cyclic AMP

• G protein

• DNA

How does cyclic AMP affect the target cell?

• It transports the hormone into the cell

• It deactivates the hormone

• It directly acts on the DNA of the target cell

• It binds to the hormone