(a)
The nervous and endocrine systems of a mammal co-ordinate responses to changes in the internal and external environment. Table 2.1 compares some features of the nervous and endocrine systems.
Complete Table 2.1.
Table 2.1
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[Maximum number: 1]
Motor neurones are cells within the nervous system.
(a)
Fig. 2.2 shows a picture of a blue whale, Balaenoptera musculus. Blue whales are the largest living mammals and have motor neurones of the type shown in Fig. 2.1. These motor neurones can be up to 30 metres long. The speed of nerve impulses along this type of motor neurone is fast.
Fig. 2.2
[ 1 ]
(i)
Suggest why fast transmission of nerve impulses is particularly important in the blue whale.
[ 1 ]
(a)
A man and a woman may be described as infertile if they have failed to conceive a child after 12 months of trying. They may opt for in-vitro fertilisation (IVF) if the woman is producing some normal eggs.
Outline the technique of IVF.
[ 5 ]
(a)
In 2009, a research laboratory for family planning in Beijing announced that it had injected 1000 healthy, fertile men with testosterone over a two-year period and found that only 10 of the men were then able to father a child. The men's normal fertility was restored six months after their last injections.
The injections, each of 500 mg of testosterone, resulted in a reduced production of follicle stimulating hormone (FSH) and of luteinising hormone (LH) in the injected men.
Describe the similarities between the effect of these testosterone injections on a fertile man with the effect of the oestrogen/progesterone contraceptive pill on production of FSH and LH by a fertile woman.
[ 3 ]
(a)
Outline the differences between the endocrine system and the nervous system.
[ 4 ]
(a)
Fig. 8.1 is a diagram summarising the role of the nervous and endocrine systems in the control of blood glucose concentration.
Fig. 8.1
With reference to Fig. 8.1, describe the role of the nervous system in the control of blood glucose concentration.
[ 4 ]
(a)
In mammals, the nervous system and the endocrine system coordinate responses to the changes in internal and external environments.
Complete Table 8.1 to indicate the differences between the nervous system and the endocrine system.
Table 8.1
[ 4 ]
(a)
Compare the endocrine and nervous systems in control and co-ordination in mammals.
[ 8 ]