# PCB 4043C Study Guide - Midterm Guide: Spartina Alterniflora, Biological Pest Control, Pioneer Species

12 pages47 viewsSpring 2014

School

University of FloridaDepartment

AgronomyCourse Code

PCB 4043CProfessor

ChristouStudy Guide

MidtermThis

**preview**shows pages 1-3. to view the full**12 pages of the document.** Your code:

Page 1 of 12

GENERAL ECOLOGY (PCB 4043)

Spring 2010

EXAM 2

• Write your code on all the pages

• Make sure that all pages are attached.

• You may not use calculators, cell phones, brain chips, or other electronic aids. The math

needed to solve a problem should be relatively simple. If you can't do the math, just

show what needs to be calculated (e.g., "answer = .5 x .3")

• If you get hung up on a problem, skip it; return to it after you’ve answered the “easy”

problems.

PAGE POINTS POSSIBLE SCORE

1 2 _____

2 6 _____

3 8 _____

4 8 _____

5 10 _____

6 10 _____

7 6 _____

8 11 _____

9 10 _____

10 11 _____

11 8 _____

12 10 _____

_____ _________

TOTAL 100 _____

1-1. (2 points for either answer) Are you interested in being an undergraduate TA for this

course next year? ( YES, NO )

###### You're Reading a Preview

Unlock to view full version

Only half of the first page are available for preview. Some parts have been intentionally blurred.

Your code:

Page 2 of 12

2-1. A student doing an independent project (Zoo 4905) monitored Daphnia growth in a

lake, and based on their performance was able to describe how the per capita growth

rate varied as a function of density. Her data are shown below.

a) (4 points) Given enough time, to what density will the population converge if

initiated at the following densities:

UFinal Density

N

0 = 1

N

0 = 3

N

0 = 7

N

0 = 14

b) (2 points) Give a biologically plausible explanation for this hump-shaped function

(your answer must be sufficiently complete to explain both the rise and fall of

the curve).

-0.4

-0.2

0

0.2

0.4

0 2 4 6 8 10 12 14

Per Capita Growth Rate,

dN/Ndt

(per week)

Daphnia Density (no. / 10 ml)

###### You're Reading a Preview

Unlock to view full version

Only half of the first page are available for preview. Some parts have been intentionally blurred.

Your code:

Page 3 of 12

3-1. (2 points) Dr. I.M. Green monitored a plant population’s density through time (note

the logarithmic scale):

Over which time period does the plant population exhibit the greatest per capita

growth rate (circle the correct option)?

i. 0-3 yrs

ii. 3-6 yrs

iii. 7-10 yrs

iv. The answer can’t be obtained from the data available

3-2. The dynamics of three species can be described using the following equations (where

N is density, in no./m2):

dN1/N1dt = +1.0 – 0.1N1 – 0.1N2

dN2/N2dt = +0.6 – 0.2N1 – 0.2N2 – 0.1N3

dN3/N3dt = –0.1 + 0.1N2

For each of the following, choose (i.e., circle) the best option from the those available

within parentheses:

a) (1 point) Species 1 and 2 are:

( competitors; predator and prey; mutualists, do not interact directly )

b) (1 point) Species 1 and 3:

( competitors; predator and prey; mutualists, do not interact directly )

c) (4 points) In the absence of Species 3, Species 1 and 2 will:

( both persist; only species 1 will persist; only species 2 will persist;

neither will persist; there is not enough information provided )

hint: for c) apply the concept of invisibility.

1

10

100

1000

012345678910

Density

time (years)

###### You're Reading a Preview

Unlock to view full version

#### Loved by over 2.2 million students

Over 90% improved by at least one letter grade.