尖瓣紫露草的向光性反应。

TROPISTIC REACTIONS OF CERIANTHUS MEMBRANACEUS.

Zoological Station, Naples, Italy.

J Gen Physiol. 1924 Mar 20;6(4):385-92. doi: 10.1085/jgp.6.4.385.

Abstract

Cerianthus shows stereotropism and if fed regularly will remain indefinitely in glass tubes. The animal retains turgor only so long as the entire surface of the body is in contact with the glass. 2. Cerianthus is positively geotropic as regards the foot and body. It will work upward into a glass tube suspended at an angle of 35 degrees as a result of stereotropism, but if the tube is raised to an angle of 45 degrees the foot turns back and the animal reverses its position in the tube so that foot is down, head, up. Thus at an angle of 45 degrees stereotropism and geotropism very nearly balance each other. 3. Light increases the muscle tone of Cerianthus; this results in positive phototropism. I x t = K. where I is the intensity of the light, t is exposure time, and K, a constant, = 0.46. Where reaction time is considered, I (t + k) = K, in which I is intensity of light, t is reaction time, k = 0.25, and K = 28.29. The two equations prove the operation of the Bunsen-Roscoe law.

摘要

海鸡冠属动物具有向性，若定期投喂，可在玻璃管中无限期存活。只要身体的整个表面与玻璃接触，动物就能保持膨胀。
海鸡冠属动物的足部和身体对地心引力具有正向性。由于向性作用，它会向上爬入一个以 35 度角悬挂的玻璃管中，但如果将管子抬高到 45 度角，足部会向后转，动物会在管子中反转位置，使足部朝下，头部朝上。因此，在 45 度角时，向性和向地性几乎相互平衡。
光增加了海鸡冠属动物的肌肉张力；这导致了正向趋光性。Ixt = K，其中 I 是光的强度，t 是暴露时间，K 是常数，等于 0.46。考虑反应时间时，I(t+k) = K，其中 I 是光的强度，t 是反应时间，k = 0.25，K = 28.29。这两个方程证明了本生-罗斯科定律的运作。