Endocrine coordination: blood carries the message
| English | 中文 | Pinyin |
|---|---|---|
| target organ/ˈtɑːɡɪt ˈɔːɡən/ | 靶器官 | bǎ qì guān |
| endocrine gland/ˈendəʊkraɪn ɡlænd/ | 内分泌腺 | nèi fēn mì xiàn |
What would explain this observation?
- A hormone travels in blood, yet only suitable targets respond. Transport through the circulation is different from an electrical impulse along a neurone.
- Start with a prediction. State the quantities or features you would compare, then decide what evidence could distinguish two explanations.
Build the model
- The endocrine system consists of glands secreting chemical hormones directly into the bloodstream. Blood carries a hormone to a target organ 靶器官, where it produces an effect. Compared with nervous responses, hormonal effects are generally slower and last longer. The pituitary in the brain releases several hormones in response to body conditions; some stimulate other glands to release hormones.
- endocrine gland 内分泌腺: A gland releasing hormones directly into blood; target organ: An organ responding to a particular hormone.
Which route describes hormonal coordination?
Locate the pituitary below the brain, thyroid in the neck, adrenal glands above the kidneys and pancreas in the abdomen. Ovaries lie in the pelvis and testes in the scrotum. These positions help identify glands on a body diagram; a gland’s position is not the location of every target it affects. The term master gland describes the pituitary’s coordinating role, not production of every hormone.
Match each technical term to its precise meaning.
Use the definitions to distinguish related quantities and processes.
Choose evidence that can test it
- Locate the pituitary below the brain, thyroid in the neck, adrenal glands above the kidneys and pancreas in the abdomen. Ovaries lie in the pelvis and testes in the scrotum. These positions help identify glands on a body diagram; a gland’s position is not the location of every target it affects. The term master gland describes the pituitary’s coordinating role, not production of every hormone.
- Label a teacher-provided body outline, then trace gland → blood → target → effect for a supplied hormone. Contrast that route with receptor → nerve pathway → effector. Use model data only; classroom investigations must not involve administering hormones or collecting sensitive personal medical information.
Which two habits make the investigation or model in this case more defensible?
Label a teacher-provided body outline, then trace gland → blood → target → effect for a supplied hormone. Contrast that route with receptor → nerve pathway → effector. Use model data only; classroom investigations must not involve administering hormones or collecting sensitive personal medical information.
Work from known quantities
- State the known values and their units. Choose the relation because its assumptions fit this case, then rearrange before substitution.
- Known: in a fictional transport model, a stated messenger travels a 30 cm route in 6 seconds. Model mean transport speed = distance/time = 5 cm per second. This arithmetic concerns the supplied model, not a universal hormone response time. Transport, target detection and the resulting cellular response are separate stages.
A supplied model route is 42 cm and transport takes 7 s. Calculate mean transport speed. Use the same sequence: known quantities → model → relation → substitution → unit and interpretation.
A supplied model route is 42 cm and transport takes 7 s. Calculate mean transport speed.
The result is 6 cm/s. Known: in a fictional transport model, a stated messenger travels a 30 cm route in 6 seconds. Model mean transport speed = distance/time = 5 cm per second. This arithmetic concerns the supplied model, not a universal hormone response time. Transport, target detection and the resulting cellular response are separate stages.
Check the conclusion and its limits
- The pancreas is a gland, while insulin is a hormone it produces. Blood distribution does not mean all cells respond identically. A hormonal response cannot be assigned a fixed universal speed from one fictional transport calculation.
- Return to the original observation. Explain what the result supports, which conditions it assumes, and one way to test a competing explanation.
The pituitary produces every hormone in the body. This claim is false: The pancreas is a gland, while insulin is a hormone it produces. Blood distribution does not mean all cells respond identically. A hormonal response cannot be assigned a fixed universal speed from one fictional transport calculation.
Endocrine coordination: blood carries the message: Locate the pituitary below the brain, thyroid in the neck, adrenal glands above the kidneys and pancreas in the abdomen. Ovaries lie in the pelvis and testes in the scrotum. These positions help identify glands on a body diagram; a gland’s position is not the location of every target it affects. The term master gland describes the pituitary’s coordinating role, not production of every hormone.
The pituitary produces every hormone in the body.
The pancreas is a gland, while insulin is a hormone it produces. Blood distribution does not mean all cells respond identically. A hormonal response cannot be assigned a fixed universal speed from one fictional transport calculation.
A gland releasing hormones directly into blood: write the technical term.
endocrine gland means A gland releasing hormones directly into blood.