I conduct an experiment to determine how increasing concentrations of nitrogen impact plant growth.  To do so, I grow groups of 5 plants with identical amounts of soil and watering schedules with either 0, 0.25, 0.5, or 1 gram of fertilizer/liter. What is the dependent variable in this experiment?

In the graph shown in the previous question, which is the dependent variable?

Which growth model describes population growth that is occurring at an increasing rate, but then slows to zero growth?

Food webs differ from food chains because food webs

Los conectores Instructions: Read the texts in questions (32-36) and select the appropriate function of the underlined phrases.

Inefficient energy transfers between trophic levels illustrate which of the following.

Which of the following is true about a positively charged atom?

Which of the following is NOT true of rivers?

Which level of ecology focuses on the interactions between the organisms, representing different species, in an area?

Review the anatomical structures that a molecule of O2 would encounter on its journey from the atmosphere to an alveolus by completing each sentence. 1. During inspiration, air passes through either the or mouth into the , a passage common to both air and food. 2. The pharynx branches into two paths: the , through which food passes to the stomach, and the , which is part of the airways and houses the vocal cords. 3. The larynx opens into a long tube, the , which in turn branches into two , one of which enters each lung. Rings of cartilage support the walls. 4. The first airway branches that no longer contain cartilage are termed . 5. Bronchioles continue branching into the , which are the final airways of the  zone. This zone contains no  and therefore has no gas exchange with the blood. 6. Alveoli first begin to appear attached to the walls of the , which then branch into the esophagusnosealveolar ductsalveolar sacsalveolibronchibronchiolesconductinglarynxpharynxrespiratoryrespiratory bronchiolesterminal bronchiolestrachea, and the airways finally end in grape-like clusters consisting entirely of alveoli, which are called .