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B. Diversity of Living Things · Diversity of Living Things

Diversity of Living Things: Unit Review

A1.2 A1.3 A1.4 A1.5 A1.6 A1.8 A1.9 A1.10 A1.12 A1.13 A2.1 A2.2 B1.1 B1.2 B2.1 B2.2 B2.3 B2.4 B3.1 B3.2 B3.3 B3.4 B3.5About 40 minutes
Learning goals
  • I can describe, name and classify the diversity of living things, from viruses to animals.
  • I can build and use dichotomous keys and sample an ecosystem, calculating density, population size and Simpson's index.
  • I can explain why biodiversity keeps ecosystems viable.
  • I can analyse how human interventions and climate change affect biodiversity.

Words to know

biodiversity
The variety of life at genetic, species, structural and ecosystem levels.
binomial nomenclature
Two-part scientific names: genus + specific epithet.
clade
An ancestor and all its descendants.
prokaryote / eukaryote
Cell without / with a nucleus and membrane-bound organelles.
dichotomous key
A series of paired choices that identifies an organism.
Simpson's diversity index
D = 1 − Σ n(n − 1) ÷ [N(N − 1)]; higher D = more diverse.
resilience
How quickly an ecosystem recovers after a disturbance.
biomagnification
Increase in a persistent toxin's concentration up a food chain.

Let's review!

In this unit you learned how biologists describe biodiversity (genetic, species, structural and ecosystem diversity), name and classify it (taxonomy, binomial nomenclature, phylogeny and cladograms), and sort it into three domains and six kingdoms, plus viruses, which are not cells at all. You explored each kingdom up close, traced how life's structures changed over 3.5 billion years, built dichotomous keys, and sampled an ecosystem using quadrats, mark-recapture and Simpson's index. Finally you explained why biodiversity keeps ecosystems viable, and analysed how human interventions and climate change affect it.

This review has a few questions from every lesson. Try each one, then press Show answer to check.

BIODIVERSITYgenetic, species, structural, ecosystemDescribe and nametaxonomy, binomial names,phylogeny, cladogramsSort3 domains, 6 kingdoms,viruses; dichotomous keysMeasuresampling, mark-recapture,Simpson's indexWhy it mattersresistance, resilience, redundancy,keystone species, servicesHow we change itinterventions (risks and benefits),climate changeHow this unit fits together
The big picture: we describe and name, sort and measure biodiversity, then ask why it matters and how human actions change it.
Eubacteriaprokaryotepeptidoglycan wallvaried nutritionArchaebacteriaprokaryoteno peptidoglycanvaried nutritionProtistaeukaryotemostly unicellularvaried nutritionFungieukaryotechitin wallsabsorbs foodPlantaeeukaryotecellulose wallsphotosynthesisAnimaliaeukaryoteno cell wallsingests foodBacteria / Archaea domainsDomain EukaryaViruses: not cells, no metabolism, no kingdom.
The six kingdoms at a glance: cell type, a key structural feature and how each gets food. Viruses sit outside the system.

Biodiversity: Genetic, Species, Structural and Ecosystem Diversity

1

Classify as genetic, species, structural or ecosystem diversity: (a) a woodlot with snags, logs and a shrub layer; (b) lake trout populations that tolerate different temperatures.

2

A plot has 24 trees: 12 sugar maple, 8 beech, 4 hemlock. Give the percentage of each.

3

Rewrite as a morphological description: "a big, weird bug."

Taxonomy: Ranks, Species and Binomial Nomenclature

1

List the eight taxonomic ranks in order.

2

Correct: "Lynx Canadensis belongs to the Felidae."

3

Two species share an order but not a family. Are they in the same class? The same genus?

4

Why are mules evidence that horses and donkeys are different species?

Phylogeny: Reading and Building Cladograms

1

What does a node on a phylogenetic tree represent?

2

Species A and B differ at 2 DNA positions; A and C at 9; B and C at 8. Which two are most closely related?

3

In the vertebrate cladogram, which trait mark separates the frog from the lizard?

Three Domains and Six Kingdoms

1

Name the three domains.

2

Multicellular, eukaryotic, chitin walls, absorbs food. Which kingdom?

3

Why was kingdom Monera split into two?

Prokaryotes, Eukaryotes and Viruses Compared

1

Give two differences between prokaryotic and eukaryotic cells.

2

How many 50 nm viruses fit along a 3 µm bacterium?

3

What is the difference between the lytic and lysogenic cycles?

4

Give one reason viruses are not placed in a kingdom.

Bacteria and Archaea: Prokaryotes Up Close

1

Describe "Gram-negative bacilli" in plain words.

2

One bacterium divides every 20 min. How many cells after 2 hours?

3

Name the three ways bacteria exchange genes.

Protists: Animal-like, Plant-like and Fungus-like

1

Name the structure each uses to move: amoeba, Paramecium, Euglena.

2

The field of view is 1.6 mm; a protist spans one-quarter of it. How long is it in µm?

3

Give two rules for biological drawings.

Fungi: Decomposers, Partners and Pathogens

1

What is a mycelium?

2

Which group forms spores in a sac of 8? On a club in groups of 4?

3

Give one way fungi help forests and one way they harm living things.

The Plant Kingdom: From Mosses to Flowering Plants

1

Put in order of evolution: seeds, vascular tissue, flowers.

2

In a fern, which generation is the large frond?

3

A plant has 2n = 24. How many chromosomes in a spore?

The Animal Kingdom: Body Plans, Invertebrates and Vertebrates

1

Classify: 8 legs, 2 body regions, no antennae.

2

What is a coelom?

3

List the four chordate features.

4

Which symmetry does a jellyfish have? A flatworm?

How Life's Structures and Functions Changed Over Time

1

Give three pieces of evidence for the endosymbiotic theory.

2

Which came first: oxygen in the atmosphere or the first animals?

3

Why is Tiktaalik important, and where was it found?

Dichotomous Keys: Identifying Organisms Step by Step

1

Fix this couplet: "1a. Insect is big; 1b. Insect has wings."

2

A key identifies 9 organisms. How many couplets?

3

Use the tree key: single, four-sided, sharp needles. What tree?

Sampling a Local Ecosystem: Methods, Ethics and the Simpson's Index

1

Mark-recapture: M = 40, C = 30, R = 6. Estimate N.

2

Calculate Simpson's D for counts 3, 3, 2 (N = 8).

3

Which sampling method suits ground beetles? Changes from shore to forest?

Why Biodiversity Keeps Ecosystems Working

1

Distinguish resistance from resilience.

2

Explain functional redundancy using pollinators.

3

What happens to kelp forests when sea otters are removed? Why?

Human Interventions: Weighing Risks and Benefits to Biodiversity

1

Explain biomagnification using DDT.

2

Give one benefit and one risk of fire suppression.

3

Rank for reliability: a government science review, an anonymous post, a company ad.

4

Name one career in biodiversity management and its training.

Climate Change and the Diversity of Living Things

1

A range edge moved 1.5° north in 30 years. Rate? (1° ≈ 111 km)

2

Explain why a cold-water specialist is more vulnerable than a generalist.

3

Name two effects of extreme water conditions on biodiversity.

Just for fun

Why did the bacterium refuse to argue with the virus about whether viruses are alive?

It said, "Come back when you have a cell of your own."

How to use this review

Do two or three sections at a time. Write your answer before you open each one. For calculations (percentages, sizes in µm and nm, bacterial growth, Simpson's index, mark-recapture, range shifts), show every step with units. For every mistake, write down why (wrong term? wrong kingdom feature? arithmetic? unit conversion?) and go back to that lesson's worked examples. Finish with the 10-question quiz.

Check your understanding

Quiz

1.

Variation in disease resistance among white ash trees is an example of:

2.

Which name is written correctly?

3.

Which pair is most closely related?

4.

Which statement about viruses is true?

5.

Purple spheres in grape-like clusters are:

6.

Which kingdom has chitin cell walls and absorbs its food?

7.

In mosses, the dominant generation is the:

8.

Mark-recapture: M = 30, C = 40, R = 5. N is:

9.

Which observation supports the endosymbiotic theory?

10.

Which change would most likely INCREASE an ecosystem's resilience?

For parents and teachers

How to use the review results:

  • Mixing up genetic, species, structural and ecosystem diversity, or percentages → revisit Biodiversity: Genetic, Species, Structural and Ecosystem Diversity.
  • Rank order, writing scientific names, species concepts → revisit Taxonomy: Ranks, Species and Binomial Nomenclature.
  • Reading or building cladograms, DNA comparisons → revisit Phylogeny: Reading and Building Cladograms.
  • Domains, kingdom criteria, absorb vs ingest → revisit Three Domains and Six Kingdoms.
  • Cell structures, viruses, lytic and lysogenic cycles, nm and µm → revisit Prokaryotes, Eukaryotes and Viruses Compared.
  • Bacterial shapes, Gram stain, growth calculations, archaea → revisit Bacteria and Archaea: Prokaryotes Up Close.
  • Protist groups, movement structures, biological drawings, field of view → revisit Protists: Animal-like, Plant-like and Fungus-like.
  • Hyphae, spore structures, mycorrhizae and lichens → revisit Fungi: Decomposers, Partners and Pathogens.
  • Plant groups, alternation of generations, chromosome numbers → revisit The Plant Kingdom: From Mosses to Flowering Plants.
  • Symmetry, body cavities, phyla, chordate features → revisit The Animal Kingdom: Body Plans, Invertebrates and Vertebrates.
  • Order of major events, endosymbiosis evidence → revisit How Life's Structures and Functions Changed Over Time.
  • Using or writing couplets → revisit Dichotomous Keys: Identifying Organisms Step by Step.
  • Density, mark-recapture or Simpson's index arithmetic → revisit Sampling a Local Ecosystem: Methods, Ethics and the Simpson's Index.
  • Resistance vs resilience, redundancy, keystone species → revisit Why Biodiversity Keeps Ecosystems Working.
  • Risk-benefit analysis, biomagnification, source evaluation → revisit Human Interventions: Weighing Risks and Benefits to Biodiversity.
  • Range shifts, mismatches, vulnerability traits → revisit Climate Change and the Diversity of Living Things.

Tip for parents: ask your teen to explain one idea from each lesson to you in their own words, without notes. Explaining is the best test of understanding.