CONCEPT QUESTION 1995: L. PETERSON/AP BIOLOGY
Angiosperms (flowering plants) and vertebrates obtain nutrients from their
environment in different ways:
(A) Discuss the type of nutrition and the nutritional requirements
of angiosperms and vertebrates.
(B) Describe 2 structural adaptations in angiosperms for obtaining
nutrients from the environment. Relate structure to function.
(C) Interdependence in nature is evident in symbiosis. Explain two
symbiotic relationships that aid in nutrient uptake, using
examples from angiosperms and/or vertebrates. (Both examples
may be angiosperms, both may be vertebrates, or one may be from
each group.
A. Types of Nutrtion and Nutrition Requirements: (MAX = 4 POINTS)
Angiosperms: Vertebrates:
(1pt) Autotrophic Described/defined (1pt) Heterotrophic Described/defined
(1pt) Require (H2O, CO2 + mineral) <--------three--------> (1pt) Require 2 different
organics + 3rd)
Carbos, fats, prot, Vit, H2O ,
minerals
(1 pt) Elaboration could be either Angiosperms or Vertebrates (1 point max)
(A) Use and function of specific element (e.g. K+ and guard cells)
(B) Macro/micro concept
(C) Citation of 3 more nutrients
(D) Process of autotrophy or heterotrophy explored
B. Structural Adaptations for Angiosperms 1st 2 structures only
(MAX = 4 POINTS)
Function Linked Structure Structural Adaptation described
Stomata e.g. pores in leaf or K+ guard cell function
Lenticel e.g. pore availability / green stems
CO2 Mesophyll e.g. loosely packed cells or surface area/uptake
Uptake Bundle sheath e.g. Special conformation around vein or CAM
Roots e.g. branched or large surface area
H2O/mineral Root hairs e.g. increase in surface area/epi-extensions
Uptake Endodermis e.g. One way 1st membrane
**Specials** Carnivorous plants (Nitrogen uptake) (e.g. Pitcher, Venus, Sundew)
Halophytes (Na/K pump root cells/Potassium uptake)
Epiphytes (chelation molecules / nutrient trap)
C. Symbiotic Relationships for Nutrient Uptake 1st 2 relationships only
(MAX = 4 POINTS)
The key to the symbiotic relationship is that the realtionship described by the student must be:
(A) continuing, and (B) highly specific
(1 point) for the relationship identified
(1 point) for the benefit to the vertebrate or the angiosperm
Possible examples are:
Mycorrhizae Mistletoe Intestinal Bacteria Nitrogen Fixers Ruminant Flora
(1 pt. max) Elaboration Exception detail Specifics Identification
Types (2) symbiotic relationships described
Impact on second symbiont
Overall Commentary on question:
The intent of this question was to test a student's understanding of both the nutrient
requirements and the adaptations that have been developed to obtain nutrients in Angiosperms
and Vertebrates. Standards were established to include pertinent and fundamental details as to:
mode of nutrition, fundamental nutritional requirements, and specific adaptations essential for both
groups. Part "C" specifically addressed symbiosis as a special relationship in Angiosperms and
Vertebrates and students were directed to explain two symbiotic relationships. When asked to
describe two structural adaptations in part B and/or two symbiotic relationships in part C, some
students gave three or more examples. Since only the first two relationships were considered for
grading, a third example, even if correct, would receive no points. Each part of this three part
question was scored at a maximum of 4 points, with the stipulation that a student could not earn a
10 unless one nutrition point was earned for Vertebrates.