Key Terms
What term describes the number of different species present in an ecosystem?
Species richness
An ecosystem has a GPP of 8000 kJ and producers use 3000 kJ in respiration. Calculate NPP.
5000 kJ
What process produces an identical copy of DNA before cell division?
DNA replication
A population graph levels off around 500 individuals. What does 500 represent?
Carrying capacity
Kangaroos gather mainly around a small number of watering holes. What distribution pattern would this most likely produce?
Clumped distribution
What type of species interaction occurs when both species benefit?
Mutualism
In a capture–recapture study, 40 animals are marked. Later, 50 are captured and 10 are marked. Estimate the population using the Lincoln index.
200
What type of succession begins on a surface where no soil is initially present?
Primary succession
wo ecosystems have the same species richness, but Ecosystem A has a more even distribution of individuals. Which ecosystem will generally have the higher SDI?
Ecosystem A
A top predator is removed from an ecosystem. What would you initially expect to happen to its prey population?
Increase
What term describes a section of DNA that contains the information used to produce a functional product?
Gene
DNA contains 32% adenine. What percentage of the DNA is guanine?
18%
What population-sampling technique involves capturing, marking, releasing and later recapturing organisms?
Capture–recapture
A transect shows plant abundance decreasing as soil salinity increases. State the relationship between salinity and plant abundance.
Negative relationship
An mRNA codon is AUG. What is the complementary tRNA anticodon?
UAC
What is a species called when it has a disproportionately large effect on an ecosystem relative to its abundance?
Keystone species
A population has 60 births, 15 immigrants, 40 deaths and 10 emigrants. Calculate the population change.
+25 individuals
What process removes introns and joins exons when pre-mRNA is processed?
RNA splicing
An energy pyramid shows 20,000 kJ at the producer level and 2,000 kJ at the primary consumer level. Calculate the percentage energy transfer.
10%
Two species compete for the same limited food source. One species is consistently better at obtaining the food. Predict the long-term outcome according to competitive exclusion.
The weaker competitor will be excluded
What term describes the actual range of conditions and resources occupied by a species after competition and other interactions restrict it?
Realised niche
Transcribe this template DNA sequence into mRNA:
3′–TAC CCG AAA GGC–5′
5′–AUG GGC UUU CCG–3′
What ecological principle states that two species occupying the same niche cannot coexist indefinitely?
Competitive exclusion principle
A graph shows enzyme activity increasing rapidly with substrate concentration, then levelling off. Explain why the curve plateaus.
The enzyme active sites become saturated, so increasing substrate concentration no longer increases reaction rate.
A DNA mutation adds one nucleotide into the coding region of a gene. Identify the mutation type and predict its likely effect on the protein.
Frameshift mutation