Population Growth and Reproduction Strategies

Flashcards covering population growth calculations, limiting factors, and r/k reproduction strategies as outlined in the lecture transcript.

What four rates determine the change in population size?

Birth, death, immigration, and emigration.

What is the formula for Population Growth ($PG$)?

$PG = (b + i) - (d + e)$, where $b$ is births, $i$ is immigrants, $d$ is deaths, and $e$ is emigrants.

What is a limitation of the Population Growth ($PG$) value calculation?

This value simply states how much the population has increased; it does not take into consideration time.

What is the formula for the Population Growth Rate ($PGR$)?

$$PGR = \frac{(\text{Births} + \text{Immigration}) - (\text{Deaths} + \text{Emigration})}{\text{Initial Population}} \times 100\%$$

What are density-independent factors?

Abiotic factors, such as temperature, water, and nutrients, that restrict population size regardless of its density.

List the specific abiotic density-independent factors mentioned in the notes.

Temperature, water, nutrients, sunlight, $pH$, salinity, and humidity.

Name three density-dependent factors.

Competition, disease, and predation.

Why is disease considered a density-dependent factor?

Disease spreads much easier in a denser population where there are more interactions between individuals.

What are the characteristics of r-strategists?

They have large numbers of offspring, provide little parental investment, and are and useful in unstable environments or where predation is high.

What are the characteristics of k-strategists?

They produce small numbers of offspring, invest extensive parental care, and live in stable environments where population is linked to density.

What type of growth curve is associated with r-strategists?

Exponential growth, which is shown as a $J\text{ Curve}$ on a graph.

What type of growth curve is associated with k-strategists?

Logistic growth, which is shown as an $S\text{ Curve}$ on a graph.

How is the reproduction strategy of trees described?

Trees show a reproduction strategy that sits between r and k strategies.

According to the syllabus objectives, what determines the carrying capacity of a population?

Limiting factors, which include both biotic and abiotic factors.

How is the cognitive verb 'Identify' defined?

To distinguish; locate, recognise and name; establish or indicate who or what someone or something is; provide an answer from a number of possibilities; recognise and state a distinguishing factor or feature.

How is the cognitive verb 'Deduce' defined?

To reach a conclusion that is necessarily true, provided a given set of assumptions is true; arrive at, reach or draw a logical conclusion from reasoning and the information given.

How is the cognitive verb 'Investigate' defined?

To carry out an examination or formal inquiry in order to establish or obtain facts and reach new conclusions; search, inquire into, interpret and draw conclusions about data and information.