Naked mole rats Q&A

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  • Created on: 11-04-13 20:48
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1. Naked mole rats show various adaptations to their particular environment. Give
an example of these adaptations exhibited by these animals.
Behavioural adaptation:
Physiological adaptation:
Anatomical adaptation:
2. Give examples of features that help thermoregulation in most mammals that are
reduced or absent in naked mole rats and explain how each operates to help achieve
1. HAIRS: these are raised in cold weather by contractions of the erector muscles ­ this
is a reflex. The aim is to trap a layer of air that insulates the body.
2. VASOCONSTRICTION: in colder conditions the muscles in the arteriole walls contract,
causing the arterioles to constrict, reducing the blood supply to the surface
capillaries. Blood flows further from the skin surface so less energy is lost.
3. VASODILATION: in warm conditions the shunt vessels constricts and the arterioles
relax. The arterioles dilate therefore blood flows closer to the surface so more
energy is lost.
4. SHIVERING: this is the uncontrolled contraction of normally voluntary muscles. It
increases heat production as it transfers energy to muscle tissue, which helps
maintain temperature.
3. Give one advantage and one disadvantage in being poikilothermic in comparison
to homeothermy.
For an important chemical reaction, poikilotherms may have four to ten enzyme systems that
operate at different temperatures. As a result, poikilotherms often have larger, more
complex genomes than homeotherms in the same ecological niche.
Because their metabolism is variable and generally below that of homeothermic animals,
sustained high-energy activities like powered flight in large animals or maintaining a
large brain is generally beyond poikilotherm animals.
4. The non-reproductive individuals in eusocial animals do not directly transfer their
genes to offspring. In spite of this there must still be a genetic advantage in being
eusocial ­ suggest what this must be.
5. What evidence would scientists look for when searching for evidence of heart
disease in naked mole rats?
6. Suggest how extra molecules attaching to proteins might affect their structure
and function.

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The centromeres split, the spindle fibres shorten, pulling the two halves of each centromere
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One chromatid of each chromosome is pulled to each of the poles.
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This is known as the reflex arc and is responsible for our reflexes - rapid, involuntary responses to
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Therefore the hypoxia resistant alleles have been passed on through the generations due to
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Firstly DNA polymerase, nucleotides, the forensic sample and DNA primers (short DNA
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