Ch.19 Population Ecology

Question 1

West Nile Virus

Answer 1

• Originated in West Nile region of Uganda in 1937, reported in NA in 1999.
• Carried by mosquito, induces fever, vomiting, headache and rash.
• Can develop encephalitis (inflammation of the brain) or meningitis (swelling of the membranes that line that skull and vertebral canal and enclose the brain and spinal cord).
• no vaccine
• high mortality rate

Question 2

population

Answer 2

A group of individuals of a single species that occupy the same general area at the same time.

• rely on the same resources
• are influenced by the same environmental factors
• are likely to interact and breed with one another

Question 3

population ecology

Answer 3

The study of changes in population size and the factors that regulate populations over time.

Question 4

size

Answer 4

number of individuals

Question 5

age structure

Answer 5

proportion of individuals of different ages

Question 6

density

Answer 6

number of individuals per unit are or volume

Question 7

population dynamics

Answer 7

Interactions between biotic and abiotic factors that cause variation in population size.

Question 8

exponential population growth

Answer 8

Describes the expansion of a population in an ideal and unlimited environment.
= (current population) x (constant rate)
constant rate = birth rate - death rate

Question 9

Logistic population growth: limiting factors

Answer 9

Environmental factors that restrict population growth and ultimately control the number of individuals that can occupy a habitat.
-food, water, shelter, space, sunlight, lvls pf potassium in the soil

Question 10

Logistic population growth: carrying capacity

Answer 10

Maximum population size that a particular environment can sustain.

Question 11

logistic population growth

Answer 11

Occurs when the growth rare decreases as the population size approaches carrying capacity. When the population is at carrying capacity, the growth rate in zero.

Question 12

density dependant factors

Answer 12

Limiting factors whose intensity is related to population density and can limit growth in natural populations.

Question 13

intraspecific competition

Answer 13

The competition between individuals of the same species for the same limited resources:
-food, shelter, nesting space, water

Question 14

density-independent factor

Answer 14

A population -limiting factor whose intensity is unrelated to population density.
-seasonal changes, fire, flood, storms

Question 15

age structure

Answer 15

A distribution of individuals in different age-groups.

-provide insight into population’s survival, reproductive success, how they relates to environmental factors

Question 16

dramatic fluctuations

Answer 16

• “Booms” = rapid exponential growth

- followed by “busts” = population falls back to a minimal level