Practice multiple choice

Question 1

Which statement about genomes is INCORRECT? Genomes

Answer 1

include all the DNA, RNA and protein in a cell at any point in time

Question 2

Which statement about the central dogma of molecular biology is
CORRECT? Information is…

Answer 2

passed from DNA to RNA to Proteins

Question 3

Which statement about RNA compared to DNA is CORRECT? RNA

Answer 3

is prone to some types of degradation whereas DNA is a more stable molecule

Question 4

Double-stranded B-DNA (the DNA double helix)

Answer 4

Involves the stacking of aromatic base pairs in the centre of the double
helix

Question 5

Which of the following is the best description of protein tertiary structure?
The

Answer 5

active 3-Dimensional shape of a single protein chain

Question 6

Enzymes usually bind:

Answer 6

One or a small number of related molecules

Question 7

When a reaction is at equilibrium:

Answer 7

The energies of the substrate and product will be equal

Question 8

the semi-conservative model of DNA replication means that:

Answer 8

After replication double-stranded helical DNA will be present as one
original and one new strand

Question 9

DNA replication involves ______________, whereas RNA transcription
involves _______________. Select the best pair of options.

Answer 9

Initiation at ORI sites / binding of transcription factors at promoter
sites

Question 10

How does tRNA contribute to the translation of a mRNA nucleotide sequence
to the corresponding protein sequence? The

Answer 10

anticodon in the tRNA base pairs to the codon in the mRNA while the
attached activated amino acid is brought close to the growing protein
chain

Question 11

Protein synthesis/translation in cells begins at _________________, and
ends with ________________. Select the best pair of options.

Answer 11

The AUG start codon / a stop codon

Question 12

During DNA replication the strands of chromosomal DNA are _________
unwound and separated before replication starts and the strands are copied
_________.

Answer 12

partly/ both 5’ to 3

Question 13

Photosynthetic and respiratory electron transport are similar because they
both produce ______ and ______, and different because only
photosynthetic electron transport produce ______.

Answer 13

a proton gradient across a membrane / ATP / O 2

Question 14

An important difference between C4 and CAM photosynthesis is that

Answer 14

C4 photosynthesis separates electron transport and the Calvin cycle in
space while CAM photosynthesis separates them in time

Question 15

Which of the following statements is CORRECT?

Answer 15

During photosynthesis, electrons are transferred from H2O to CO 2,
while during respiration electrons are transferred from glucose to H2O

Question 16

The Krebs cycle produces

Answer 16

NADH, CO 2 and FADH2

Question 17

The products of the photosynthetic electron transport chain are

Answer 17

O 2, ATP, NADPH

Question 18

Which of the following statements is CORRECT?

Answer 18

Catabolism is the breakdown of molecules, involves a decrease in
atomic order, an increase in entropy and NADH

Question 19

Which of the following statements is CORRECT? In plant cells, the

Answer 19

electron transport chains produce proton gradients in the cristae of
mitochondria

Question 20

At low CO 2 concentrations, Rubisco..

Answer 20

Can act as an oxygenase, when it reacts with O 2 to produce a 3-carbon
and a 2-carbon product

Question 21

An important difference between C4 and C3 photosynthesis is that

Answer 21

PEPC is the initial carboxylating enzyme in C4 photosynthesis

Question 22

The production of ___________________ from ________________ is an
example of _____________________ metabolism.

Answer 22

glucose / glycogen / catabolic

Question 23

Amino acids in the lumen of the small intestine are actively absorbed through
______________ tissue cells which are located on a/an ____________ and
the amino acids are transported into a capillary.

Answer 23

epithelial / villus

Question 24

An important step in the evolution of the eukaryotic cell from a prokaryotic
cell was the _________________ of _____________________ to form the
nucleus and ____________________.

Answer 24

invagination / the plasma membrane / endoplasmic reticulum

Question 25

Prokaryotic and eukaryotic cells both ______________ but only prokaryotic cells can have _____________________ and ___________________ .

Answer 25

have a contractile ring that separates a dividing cell / pili / a capsule

Question 26

In a __________________ cell __________________ is imported via _________________ and transported to the _________________ .

Answer 26

macrophage / low density lipoprotein / endocytosis / lysosome

Question 27

In a nerve cell __________________ is/are transported from the ________________ to the _________________ of the cell and this process is powered by ATP that phosphorylates the transporter proteins thus causing a(n) _______________ and a conformational change.

Answer 27

sodium ions / cytoplasm / exterior / change in the interaction between R groups

Question 28

The _______________ of epithelial cells is/are directly attached to ________________ that is/are _____________________ .

Answer 28

basal aspect / the basal lamina / composed of connective tissue

Question 29

The blood vessels are always lined with ______________. _________________ is found in every hollow organ except the heart

Answer 29

epithelium / smooth muscle

Question 30

Pasteur’s experiment with swan-necked flasks was used to prove:

Answer 30

That there is no “life force” in the air

Question 31

Which of the following statements regarding the most recent version of the tree of life is INCORRECT?

Answer 31

There are three major groups, the bacteria, the animals and the plants

Question 32

Bacteria help ruminants digest cellulose but they also

Answer 32

produce methane, which is a greenhouse gas

Question 33

Which of the following statements regarding fermentation is INCORRECT?

Answer 33

it can be done by yeasts but not bacteria

Question 34

Pollutant-degrading bacteria typically belong to which of the following nutritional types?

Answer 34

Heterotrophs

Question 35

Which of the following statements regarding microbial biodiversity is CORRECT?

Answer 35

Many microbes are only known about through DNA sequencing

Question 36

Yeasts have which of the following advantages over bacteria for cloning genes?

Answer 36

Better capacity to express cloned eukaryotic gene

Question 37

What valuable resource do the Archea offer for biotechnology? They

Answer 37

make thermostable enzymes like DNA polymerase

Question 38

Succession is a theory about how ecological communities change over time. After a community has been disturbed, what are the three main models that describe how succession might proceed?

Answer 38

Inhibition, tolerance and facilitation

Question 39

In order to determine if an animal is foraging optimally in a landscape consisting of two types of food, low and high quality, what is the most important piece of information to know? The

Answer 39

relative abundance of the two resources

Question 40

Which of the following lists contain taxa that are uniquely (all members of the taxa belong to the same category) a true predator, a grazer, and a parasite (in that order)?

Answer 40

Owl, limpet, tapeworm

Question 41

The amount of energy passing through an ecosystem is determined by the:

Answer 41

net primary productivity of the ecosystem =

Question 42

An ecotone can be defined as a

Answer 42

transitional area between two or more habitats or communities E. transitional area between stages in succession

Question 43

Which of the following ecosystem orders describes a general trend of increasing primary productivity?

Answer 43

Deserts, grasslands, forests

Question 44

European red foxes and feral cats have been introduced to many parts of the world, but these predators have caused more extinctions of native mammal species in Australia than in any other large land area. This is most likely because

Answer 44

Native Australian mammals did not evolve with foxes and cats and hence have not evolved defences against these predators

Question 45

A field experiment in ecology can be considered well designed if, at minimum, it

Answer 45

uses replicated control and experimental treatments

Question 46

In biology, the concept of 'evolutionary fitness' is usually taken to mean

Answer 46

an individual's relative contribution to the next generation's gene pool

Question 47

A group of organisms of the same species living in a geographically distinct area is defined as a:

Answer 47

Population

Question 48

An ecologist would use which of the following methods to measure α- diversity.

Answer 48

count the number of species in a local area

Question 49

How do you BEST demonstrate your measurements of Lactate Dehydrogenase (LDH) activity are a quantitative measure of the amount of enzyme present in the sample

Answer 49

By adding different amounts of LDH enzyme to the reaction and showing a proportional rate response

Question 50

When measuring growth of plants in different environmental conditions, which would be the most representative, most reliable and easiest measurement?

Answer 50

Leaf area of all leaves per plant

Question 51

If you place an animal cell in a hypotonic solution, it will look______________. If you place a plant cell in a hypotonic solution it will look______________. Select the best pair of options

Answer 51

Lysed / turgid

Question 52

This question relates to the plates exposed in different locations in Sydney. What is the most accurate statement about your observations?

Answer 52

Fungal abundance, diversity and morphology was different

Question 53

Micrococcus luteus was used during a practical class to demonstrate a pattern of transmission using lollies and handshaking. Which of the following statements in relation to the use of M. luteus in this experiment is INCORRECT?

Answer 53

The Micrococcus sp. associated with the normal microflora of the participants’ hands will not confound the results because students were asked to wash their hands thoroughly to eliminate all microbes.

Question 54

A spread plate inoculated with 100μl taken from a 1ml suspension of 10-4 dilution mixture of soil/PBS has a total count of 55 colony forming units. Calculate the cfu in 1ml of the diluted sample.

Answer 54

5.5 x 10 2 cfu/ml

Question 55

An ecologist has $850,000 to invest into decreasing the risk of extinction of a unique population of flightless bird. Using known demographic data of the population, the ecologist models two possible scenarios, using the program Vortex, and compared those scenarios to the current population’s probability of survival (basic model). Based on the model outputs below, and your understanding of Vortex, where should the ecologist invest the money?

Answer 55

Rearing chicks in the lab and releasing them in order to reduce juvenile mortality from 80% to 70%.

Question 56

You want to estimate the population size of a blue tongue lizards in a residential precinct using a Peterson’s estimate. Using traps, you capture, tag and release 12 lizards during your first sampling period. In your second sampling period you capture six (6) lizards, two (2) of which are marked. What is your estimate of the population of blue tongue lizards in the park?

Answer 56

36

Question 57

In one of your practicals, as a class you assessed the impacts of contamination in Sydney Harbour by assessing differences in assemblages of benthic infauna at Chowder Bay and Blackwattle Bay. Which was the BEST conclusions that you should draw form your class results?

Answer 57

There are differences in the assemblage of benthic infauna at Blackwattle Bay compared to Chowder Bay, but we cannot be sure that these differences are due to contamination or another aspect(s) of the two sites.

Question 58

How does the conversion of pyrophosphate (diphosphate) to phosphate molecules help drive the formation of phosphodiester bonds, and other thermodynamically unfavourable interactions?

Answer 58

This reaction is favourable and provides the energy for an unfavourable (2) reaction - AND It uses up products of the first reaction (pyrophosphate) driving the equilibrium towards formation of more pyrophosphate (and therefore also phosphodiester bonds).

Question 59

Describe the similarities and differences of DNA replication on the leading strand and the lagging strand (you can use sketches to illustrate your answer)

Answer 59

On the leading strands, once an RNA primer has been placed, DNA polymerisation is continuous in a 5’-3’ direction (2) - On the lagging strand the DNA is running the wrong direction for continuous replication, so a series of primers must be put down, the DNA replicated in pieces, the RNA primer removed and the pieces of DNA filled in, and ligated (4)

Question 60

How did eukaryotic cells evolve

Answer 60

The hypothesis that eukaryotic cells evolved from a symbiotic association of prokaryotes—endosymbiosis—is particularly well supported by studies of mitochondria and chloroplasts, which are thought to have evolved from bacteria living in large cells.

Question 61

describe the photosynthetic electron transport including the enzyme complexes and major products

Answer 61

The photosynthetic electron transport chain involves the coordinated action of Photosystem II, plastoquinone, the cytochrome b6f complex, Photosystem I, and the enzyme ferredoxin-NADP+ reductase. The major products of this process are ATP and NADPH, which are crucial for the subsequent dark reactions (Calvin cycle) of photosynthesis, where they are used to fix carbon dioxide into organic molecules.

Question 62

cloning vector amp purpose

Answer 62

Codes for ampicillin resistance Is a selectable marker, which allows us to “force” the cells to take up the plasmid and identify the colonies that contain it. Only cells with the amp gene will be able to survive on an ampicillin plate

Question 63

cloning vector ori genes purpose

Answer 63

These genes encode replication functions. They ensure that the plasmid will be able to replicate and therefore to persist in the host.

Question 64

Clonging vector the polylinker site

Answer 64

This is the cloning site. We cut open the plasmid and insert the foreign genes into this site

Question 65

Draw an outline diagram of a trophic cascade. This should have three levels

Answer 65

predator --> prey --> plant