| Some keys use paired choices of features to identify species such as the ant- mimic jumping spider. State the name of this type of key. | dichotomous key. |
| state two common features of all the arthropods. | exoskeleton, few pairs of jointed legs. |
| State two common features of all arachnids that can be used to distinguish them from other arthropods. | Four pairs of jointed legs, two body parts, fused head and thorax |
| Many traditional methods of classification used morphology. State the name of three other type of features that can also be used in classification. | anatomy, DNA, genes, sequences of amino acids. |
| Scientists think that the pattern on the bodies of the spider is an adaptive feature. Explain the term adaptive feature with reference to this pattern. | inherited feature/ controlled by gene/ DNA
increase chance of survival
increase chance of reproducing- to leave offspring
camouflage/ scares predators/ lure for prey |
| DNA can be extracted from the webs of spiders. This DNA can be used to identify the species of spider that made the web, and the species of prey caught in the web.
Explain how DNA extracted from spider webs can be used to identify different species. | Each species has unique DNA/ genes
If a match with DNA from known species then DNA from closely related species have fewer differences in their base sequences. |
| State three feature of monocotyledons that can be used to distinguish them from dicotyledons. | Monocotyledons have parallel veins, strap- shaped leaves, one cotyledon and flower petals in multiples of three |
| State two features of myriapods that can be used to distinguish them from other arthropods. | 1.many pairs of jointed legs
2. many body segments |
| State the names of all the arthropods | myriapods, crustaceans, arachnids and insects |
| Bacteria are classified in the prokaryote kingdom.
State two features of animal cells that are no found in bacteria | nucleus, mitochondria, rough endoplasmic reticulum |
| Describe and explain what happens to the number of live bacteria shown in the stages labelled A, B, C and D | A is the lag phase
- bacteria growing / dividing slowly- bacteria adjusting to conditions/ absorbing resources/
B is the exponential phase
- resources are not limiting, bacteria growing/ dividing rapidly, growth birth greater than death rate
C is the stationary phase
-birth rate= death rate
D is the death phase
- death rate greater than birth rate
C/ D
- many bacteria dying, resources become limiting, space become limiting, toxins build up. |
| what is a species | species is a group of organism that can reproduce to produce fertile offspring. |
| The presence of hair is a feature that is only found in mammals.
State two other features that distinguish mammals from other vertebrates | 1. have fur
2. young feed on milk.
3.four different types of teeth/ sweat glands/ placenta/ diaphragm |
| State the name of the parts of the virus shown in figure 6.1 labelled X and Y | X: protein coat
Y: RNA |
| Define the term decomposer. | Decomposer are organisms that get energy from dead/ waste organic matter. |
| State two features, visible in the picture, that identify Arctic wolves as mammals. | 1. have hair/ fur
2. external ear |
| A. virginiensis releases the poison cyanide when it is attacked by predators.
Cyanide stops enzymes in the mitochondria from functioning.
Suggest why cells die if the mitochondria do not function. | Mitochondria provides energy, it is a place where aerobic respiration takes place. Without mitochondria, cells are not able to carry out the processes of life. |
| Bacteria belong to the Prokaryote kingdom.
State two ways in which the structure of bacteria differs from the structure of viruses.
1 ........................................................................................................................................
2 ........................................................................................................................................ | cell wall ;
cell membrane ;
cytoplasm ;
loop of DNA ;
(slime) capsule ;
flagella ;
plasmid ;
ribosome ; |
| (ii) State two features that are present in plant cells that are not present in the cells of reptiles.
1 ........................................................................................................................................
2 ........................................................................................................................................ | cellulose / cell wall ;
chloroplast / chlorophyll ;
starch grains ;
(large / permanent / central) vacuole ; |
| Some fungi and bacteria are decomposers.
Define the term decomposer. | organisms that get energy from dead / waste, (organic) material ; |
| State three visible features from Fig. 5.1 that could be used to distinguish adult insects from other arthropods. | three pairs of legs ;
three (named) body segments ;
wings ;
(pair of) antennae ;
compound eyes ; |
| State the name of the kingdom that bacteria belong to. | prokaryote ; |
| State one similarity between the structure of bacteria and the structure of viruses. | presence of genetic material / DNA / RNA ;
presence of protein ; |
| Write the formula that would be used to calculate the actual length of the bacterium (not including the flagellum)
The actual length of the bacterium shown in Fig. 1.3 is 0.0026mm.
Convert this value to micrometres (µm). | (actual length of bacterium) = size / length, of the image ÷ magnification ;
2.6 (µm) ; |
| State two other features of all viruses. | genetic material ;
protein coat ;
parasitic / pathogenic ;
only reproduce in a host / do not show (other) features of living
organisms / AW ;
very small ;
they are not cellular / absence of named organelle;
AVP ; cannot be killed / cannot be treated, with antibiotics. |
| Suggest one feature that could be used to classify viruses into groups. | shape / size / AW ;
genetic material (sequence / type) ;
host species / type of disease it causes ;
AVP ; |
| State the genus of Helicobacter pylori | Helicobacter ; |
| State the function of mitochondria. | respiration ;
aerobic (respiration) ;
release energy / make ATP ; |
| State two characteristics of fungi that are used to distinguish them from plants. | different composition of cell wall ;
no, chlorophyll / chloroplasts / heterotrophic ;
extracellular digestion / saprophytic / decomposer / AW ;
hyphae / mycelium ;
no (central) vacuole ;
AVP ; |
| Yeast is a single-celled fungus that is used in bread-making.
Explain why yeast is used in bread-making. | respiration / fermentation ;
carbon dioxide released ;
(bubbles / carbon dioxide) causes, dough / bread, to rise ;
(yeast produces) enzymes ;
enzymes / amylase, digest starch ;
AVP ; |
| State one feature shown by all dicotyledonous plants. | two cotyledons ;
broad leaves ;
leaves with branching veins ;
petioles ;
flower parts in multiples of four or five / flower parts not in threes ;
pollen with three furrows or pores ;
stem vascular bundles in a ring ;
roots, develop from radicle ;
AVP ; |
| Give two features that differ birds from other animals. | • feathers
• beak / bill
• hard-shelled eggs
• scaly legs
• no teeth
• air sacs
• light-weight skeletons
• AVP |
| State two features of all prokaryotes. | no nucleus ;
cell wall ;
loop of DNA ;
AVP ;; |
| Modern methods of classification rely on the analysis and comparison of base sequences inn DNA.
Describe the type of evidence that scientists used for classifying organisms before they were able to sequence DNA. | 1 study, similarities / differences in, morphology / appearance / phenotype / features/ characteristics / shape;
2 any example; e.g. presence or absence of wings
3 study, similarities / differences in, anatomy / internal structure of organisms;
4 any example; e.g. skeleton / organs /bones /teeth
5 AVP; study, similarities /differences in, any other type of evidence
6 AVP; any example of the type of evidence given |
| question in picture | 2(c)(i) A and B/Aspergillus flavus and A. oryzae;
2(c)(ii) long(est) distance from the branching point;
branched / split, the longest time ago;
no other species on its branch /AW;
only one ancestor (in the diagram);
many differences in base sequence (from the others); |
| Describe how the students should use the measuring cylinder to obtain accurate
measurements of volume. | read at eye level / avoid error of parallax;
read bottom of meniscus;
place measuring cylinder on a level / flat, surface;
remove funnel / ensure all drops have fallen to the bottom;
A parallel /horizontal to meniscus |
| The students performed four experiments using different ways to prepare the apples.
The same total mass and type of apple was used each time.
A 0.5cm3 apple cubes
B 1.0cm3 apple cubes
C whole peeled small apples
D whole unpeeled small apples
Predict and explain which experiment (A, B, C or D) would result in the fastest rate of reaction. | A/ 0.5 (cm3 cubes);
large(st) surface area (to volume); |
| State the function of mitochondria. | respiration;
aerobic (respiration);
release energy / make ATP; |
| Some scientists think that mitochondria evolved from bacteria because they are similar in size and structure. Bacteria belong to the Prokaryote kingdom.
Give two features of all prokaryotes. | cytoplasm;
cell membrane;
single celled / unicellular;
no (true) nucleus / no nuclear membrane;
loop of DNA/ chromosome / naked DNA;
no, (membrane-bound) organelles /mitochondria
/ chloroplasts;
(peptidoglycan / murein) cell wall;
AVP; e.g. plasmids |
| Suggest why using DNA sequences is a useful method for identifying species of bacteria. | it is (more) accurate (than traditional classification systems);
easi(er)/ cheap(er)/ quick(er)/(more) efficient/ to use (than
other (named) identification methods); ora
allows large-scale identification (of many species
simultaneously);
only trace samples are required;
(DNA sequences) within a species are very similar; |
| Name one feature of dicotyledonous leaves that distinguishes them from monocotyledonous leaves. | (branching) veins; ora
shape /broad (leaves); ora |
| Bacteria are prokaryotes.
State two distinguishing features of all prokaryotes. | single celled/ unicellular ;
no (true) nucleus / no nuclear membrane ;
loop of DNA ;
no, (membrane-bound) organelles ; e.g. no mitochondria / chloroplasts
(peptidoglycan/murein) cell wall ;
reproduce by binary fission ;
small(er) / 70S, ribosomes ;
plasmids ; |
| Suggest the function of the flagellum in bacteria | swim / movement / AW ; |
| Forensic scientists often try to find DNA on items of stained clothing. The DNA can be used to identify individual people.
Suggest why DNA can be used to identify individual people. | individual people have, different / unique, DNA ;
DNA has genes or alleles have, sequences of bases ;
AVP ; |
| State two structural features that distinguish the cells of a protoctist from a prokaryote. | assume features are of protoctists unless told otherwise
nucleus / nuclear membrane / nuclear envelope ;
(named) organelle(s) / internal membranes ;
cell walls (if present) have different composition ;
linear chromosomes ;
AVP ; |
| State two features that distinguish leaves of dicotyledonous plants from leaves of
monocotyledonous plants. | network / branched, veins ;
broad (leaves) ;
petiole ;
AVP ; |
| State the name of the structures inside cells that assemble amino acids into proteins. | ribosomes / (rough) endoplasmic reticulum |
| State two features of animal and plant cells that are not found in prokaryotes. | nucleus / nuclear membrane / nuclear envelope ;
(linear) chromosomes ;
mitochondrion ;
endoplasmic reticulum ;
vacuoles / vesicles ;
AVP ; |
| Mitochondria have two membranes, an inner membrane and an outer membrane. The inner membrane is folded and used in respiration.
Suggest why the inner membrane of mitochondria is folded. | large surface area ;
more surface for respiration ;
allows, increased/ faster/ efficient, respiration ; |
| Explain the differences between the average numbers of mitochondria in the cells shown in Table 1.1. | 1 mitochondria are site of aerobic respiration/production of (most of the) ATP ;
2 liver cell/ heart cell, is very active/ use lots of energy /respire more ;
3 e.g. function of liver cell or heart cell ; e.g. active transport/ making
enzymes / making bile/ muscle contraction/ heart pumping
4 sperm cells, are active/ swim/ beating flagella ;
5 sperm cells have few mitochondria, as they are small ;
6 red blood cells, full of haemoglobin/ more space for oxygen/AW ;
7 red blood cells, use less energy / do not actively move ; |
| Describe how DNA can be used to classify organisms. | the sequence of bases in DNA are used ;
base sequences /DNA/ genes, that are more similar mean that organisms are
more closely related ; ORA |
