Question
Needle-like crystals of either aragonite (“uh-RAG-uh-nite”) or calcium bound to this anion are called raphides (“RAFF-id-eez”) and are found in the idioblasts (“ID-ee-oh-blasts”) of plants like pineapples and calla lilies. For 10 points each:
[10m] Name this ion used by some plants as a sink to help regulate apoplastic calcium concentrations. High dietary intake of this ion is a risk factor for kidney stones.
ANSWER: oxalate (“OX-uh-late”) [or C2O4 2− (“C-two-O-four-two-minus”)]
[10e] Calcium oxalate crystal formation in idioblasts would overload cells with calcium without an abundance of this membranous organelle to sequester it. This organelle has smooth and rough subtypes.
ANSWER: endoplasmic reticulum [or ER; accept sarcoplasmic reticulum or SR]
[10h] Oxalate crystal sequestration may also be involved in plant tolerance to this metal, whose toxic plus-three cation (“CAT-eye-on”) limits root growth in acidic soil.
ANSWER: aluminum [or Al; or aluminium]
<Biology>
Summary
| 2023 ACF Nationals | 04/22/2023 | Y | 8 | 16.25 | 100% | 25% | 38% |
Data
| Chicago A | Houston A | 10 | 10 | 0 | 20 |
| Chicago B | Virginia A | 0 | 10 | 10 | 20 |
| Claremont A | Stanford A | 0 | 10 | 0 | 10 |
| Toronto A | Purdue A | 0 | 10 | 0 | 10 |
| UC Berkeley A | North Carolina A | 0 | 10 | 0 | 10 |
| UC Berkeley B | Yale A | 10 | 10 | 10 | 30 |
| Cornell A | Iowa State A | 0 | 10 | 0 | 10 |
| Florida B | Georgia Tech A | 0 | 10 | 10 | 20 |