A Unity and Diversity

A1.1 Water

A1.2 Nucleic acids

A2.1 Origins of cells

A2.2 Cell structure

A2.3 Viruses [HL only]

A3.1 Diversity of organisms

A3.2 Classification and cladistics [HL only]

A4.1 Evolution and speciation

A4.2 Conservation of biodiversity

B Form and Function

B1.1 Carbohydrates and lipids

B1.2 Proteins

B2.1 Membranes and membrane transport

B2.2 Organelles and compartmentalization

B2.3 Cell specialization

B3.1 Gas exchange

B3.2 Transport

B3.3 Muscle and motility [HL only]

B4.1 Adaptation to environment

B4.2 Ecological niches

C Interaction and Interdependence

C1.1 Enzymes and metabolism

C1.2 Cell respiration

C1.3 Photosynthesis

C2.1 Chemical signalling [HL only]

C2.2 Neural signalling

C3.1 Integration of body systems

C3.2 Defence against disease

C4.1 Populations and communities

C4.2 Transfers of energy and matter

D Continuity and Change

D1.1 DNA replication

D1.2 Protein synthesis

D1.3 Mutation and gene editing

D2.1 Cell and nuclear division

D2.2 Gene expression [HL only]

D2.3 Water potential

D3.1 Reproduction

D3.2 Inheritance

D3.3 Homeostasis

D4.1 Natural selection

D4.2 Stability and change

D4.3 Climate change

IB Biology HL A3.2 Classification and cladistics [HL only] Question Bank

[Maximum number: 1]

The black-legged tick (lxodes scapularis) is an arthropod which sucks blood from humans and other mammals. It is encountered mainly in wooded and semi-wooded areas.

Some ticks can be infected by the bacterium Borrelia burgdorferi. When a tick bites a human, the bacterium is often introduced, causing Lyme disease. Lyme disease is a public health problem in North America and, if left untreated, can cause important neurological impairment. The diagram represents the two-year life cycle of a tick.

(a)

State the domain into which ticks are classified.

[ 1 ]

(a)

Define clade.

[ 1 ]

(a)

The table shows certain characteristics present (+) or absent (-) in six organisms.

Using the data, label the cladogram with the names of the organisms.

[ 3 ]

(a)

The diagram shows part of a cladogram for invertebrate species from the Cambrian age.

[ 2 ]

(i)

On the cladogram, label with the letter C the point that shows the most recent common ancestor of Pambdelurion and Fuxianhuia.

[ 1 ]

(ii)

Identify which two species evolved most recently.

[ 1 ]

[Maximum number: 4]

Molecular visualization software was used to produce the representation of a human nucleosome.

(a)

Explain how DNA can be used in cladistics.

[ 4 ]

[Maximum number: 6]

Discuss the use of cladograms in phylogenetic studies.

[Maximum number: 6]

Discuss the use of cladograms in classification and research into the evolutionary origins of living organisms.

[Maximum number: 6]

Explain cladistics as a method of classifying organisms.

[Maximum number: 1]

The table compares ribosomal RNA (rRNA) sequences of two organisms from each of the three domains by showing an association coefficient. The more similar the rRNA sequences of the organisms, the larger the coefficient.

What can be concluded from the data?

L. minor and E. coli are both eubacteria.

S. cerevisiae and M. barkeri are in the same domain.

M. ruminantium is an archaean, therefore so is B. firmus.

E. coli and B. firmus are in the same domain.

[Maximum number: 1]

Which encircled area shows a clade?

0 selected

Question 1

Question 1(a)

Question 2

Question 2(c)

Question 2

Question 2(a)

Question 2

Question 2(b)

Question 2(b)(i)

Question 2(b)(ii)

Question 2

Question 2(c)

Question D3

Question 3

Question 3

Question 17

Question 17