首页
登录
职称英语
[originaltext] Human population near the equator have evolved dark skin over
[originaltext] Human population near the equator have evolved dark skin over
游客
2024-01-03
56
管理
问题
Human population near the equator have evolved dark skin over many generations because of exposure to the fiercest rays of the sun. A similar phenomenon has also occurred in other parts of the animal kingdom. The African grass mouse is a good example. Most mice are nocturnal, but the African grass mouse is active during daylight hours. This means that it spends its days searching for food in the semi-dry bush in squired habitats of eastern and southern Africa. Its furry stripe’s like a chipmunk’s, which helps it blend in with its environment.
Because it spends a lot of time in the intense tropical sun, the grass mouse has also evolved two separate safeguards against the sun’s ultraviolet radiation. First, like the population of humans in this region of the world, the skin of the grass mouse contains lots of melanin, or dark pigment. Second and quite unusual, this mouse has a layer of melanin pigmented tissue between its skull and skin. This unique cap provides an extra measure of protection for the grass mouse and three other types of African mouse, like rodents that are active during the day. The only other species scientists have identified with the same sort of skull of that occasion is the white camp-making bat of the Central American tropic. Although these bats sleep during the day, they do so curled up with their head exposed to the sun.
选项
A、It has a flattened shape
B、It has an extra layer of pigmented tissue
C、It has a furry covering
D、It has a large cranial cavity
答案
B
解析
What is unusual about the head of African grass-mouse?
转载请注明原文地址:http://tihaiku.com/zcyy/3331217.html
相关试题推荐
Choosethecorrectletter,A,BorC.[br]Derrickbelievesthat[originaltext]A
[img]2022m3x/ct_ve01202001m_eillist_1180_220329[/img][br][originaltext](A=Age
[img]2022m3x/ct_ve01202001m_eillist_1180_220329[/img][br][originaltext](A=Age
[img]2022m3x/ct_ve01202001m_eillist_1180_220329[/img][br][originaltext](A=Age
[img]2022m3x/ct_ve01202001m_eillist_0350_220329[/img][br][originaltext]The2-
[img]2022m3x/ct_ve01202001m_eillist_0276_220329[/img][br][originaltext]Thism
[img]2022m3x/ct_ve01202001m_eillist_0276_220329[/img][br][originaltext]Thism
[img]2022m3x/ct_ve01202001m_eillist_0276_220329[/img][br][originaltext]Thism
[img]2022m3x/ct_ve01202001m_eillist_0276_220329[/img][br][originaltext]Thism
[img]2022m3x/ct_ve01202001m_eillist_0276_220329[/img][br][originaltext]Thism
随机试题
Accidentsarecaused;theydon’tjusthappen.Thereasonmaybeeasytosee:
Somesocialscientistshaveclaimedthatdivorceharmschildrenfortheres
PartⅡReadingComprehension(SkimmingandScanning)Directions:Inthispart,y
Theymayhavecreatedappealingvisualswiththeirfavouritecoloursonpaper
工程管线在交叉点的高程应根据何种管线高程确定?( )A.给水管 B.排水管
用魏氏法测定ESR,错误的是A.使用管长300mm,管孔内径5mm的血沉管 B
患儿,8个月。单纯母乳喂养,从未加辅食。近来面色蜡黄,表情呆滞,舌面光滑,有轻微
膳食脂肪中饱和脂肪酸、单不饱和脂肪酸和多不饱和脂肪酸的最佳比例为A.1:1:1
地铁车站附属建筑物包括( )。A.通风道 B.风亭 C.出入口 D.冷却塔
有关DNA双螺旋结构的叙述,错误的是( )。A.DNA双螺旋是核酸二级结构的重
最新回复
(
0
)