Question

A molecule binds and blocks a potassium channel in a plant cell membrane. What would be its effects?

Potassium uptake would be blocked because the proton pump would no longer work.

Potassium uptake would be unchanged since potassium readily crosses through the cell membrane's lipid bilayer.

Potassium uptake would be blocked since potassium ions enter cells through facilitated diffusion.

Potassium uptake would be unchanged since uptake is by active transport by pumps.

2. What nutritional benefits can insects provide to carnivorous plants?

The carnivorous plant Nepenthes bicalcarata ("fanged pitcher plant") has a unique relationship with a species of ant − Camponotus schmitzi ("diving ant"). The diving ants are not digested by the pitcher plants, but instead live on the plants and consume nectar. Diving ants also dive into the digestive juices in the pitcher, swim to the bottom, and capture and consume trapped insects, leaving uneaten body parts and ant feces behind. What nutritional impact do the ants have on fanged pitcher plants? Do the pitcher plants derive any nutritional benefit from this relationship?

Part A

Researchers tested the hypothesis that the relationship between diving ants and pitcher plants is mutualistic (i.e., both species derive a nutritional benefit). To do so, they compared leaf surface area (as a measure of overall growth) in two sets of pitcher plants: plants with diving ants and plants without. The results are shown in the graph. The P values indicate whether or not there is a significant relationship between the size of the host plants and the surface area of the host plants' leaves. Based on this graph, what conclusions can be drawn about the impact of diving ants on overall plant growth?

Source: Bazile, V. et al. 2012. PLoS ONE 7: e36179.

the terms on the left to the appropriate blanks on the right to complete the sentence

positive

negative

with

without

Plants ______ diving ants show significantly larger total leaf surface area than plants ants. Plants ________ ants grow taller without any significant increase in leaf surface area. In plants ______ ants, however, leaf surface increases significantly as the plants grow taller. Therefore, diving ants have a ______ impact on overall plant growth.

Please answer all four blanks from above options.

With ants P

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