章节大纲

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    Case Study Conclusion: Wearing His Heart on His Sleeve
    ::案例研究结论:用他的袖子穿戴他的心

    Are you still wondering whether Keith—who you read about in the beginning of this chapter—actually got a tattoo of his new girlfriend’s name on his arm? The photograph above is your answer! Let’s hope his love for Larissa—and for the artwork—lasts as long as his tattoo. According to a poll conducted in 2012 by Harris Interactive, 14 percent of American adults regret getting a tattoo. Although laser tattoo removal is available, it does not always work fully, can cause pain and scarring, and is expensive and time-consuming. Some people who regret a tattoo opt instead (or additionally) to cover it with another tattoo, see photo . 
    ::你是否还在想Keith — — 你在本章开头所读到的Keith — — 是否实际上在他的手臂上有一个他新女友名字的纹身?上面的照片就是你的答案!让我们希望他对Larissa的爱 — — 以及艺术作品的爱 — — 只要他的纹身就一直存在。 根据2012年Harris Bitactive的民意调查,14%的美国成年人对纹身感到后悔。 尽管激光纹身的去除并不总是完全有效,但它有时会造成疼痛和疤痕,而且费用昂贵且耗时。 有些人对纹身选择用另一纹身覆盖它感到后悔(或者更多),请看照片。

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    This man got his carrot tattoo partially removed using a laser, and then covered it with a new tattoo of flowers.
    ::这个人用激光除去他的胡萝卜纹身 然后用花的新纹身遮盖

    Why are tattoos essentially permanent? Tattoos are created  by inserting a needle containing pigment through the epidermis and into the dermis of the skin. The pigment is injected into the dermal layer, creating the design. The pigment can remain in the dermal layer for a person’s lifetime for a few  reasons. One, unlike the thinner outer epidermal layer, the dermis is not continually shed and replaced, so the pigment generally stays put. Two, the pigments used in tattooing mainly consist of large particles. When you get a tattoo, the penetration of the skin and insertion of foreign particles causes an immune response in which white blood cells attempt to engulf and remove the pigment. B ecause most of the pigment particles are so large, however, they cannot be removed from the dermis by the immune cells, and the design remains.
    ::为什么纹身本质上是永久性的?纹身是通过在皮肤皮层和皮肤皮质中插入含有色素的针头来创建的。颜料被注入皮肤层,从而设计设计。颜料可以在一个人的一生中留在皮肤层中,有几个原因。 第一,与薄薄的外皮层不同,皮肤没有不断脱落和替换,因此颜料一般不动。 第二,纹身中使用的颜料主要由大颗粒组成。 当你得到纹身、皮肤穿透和插入外来粒子时,白血细胞试图吞没并并去除色素,从而产生免疫反应。 由于大部分色素粒如此之大,免疫细胞无法将它们从皮质中去除,设计留下。

    In laser tattoo removal, pulses from a high-intensity laser are applied to the tattoo and absorbed by the pigments. This breaks up the large pigment particles into particles that are small enough to be removed by the immune system. The pigments may then be excreted out of the body, or moved to other areas of the body, such as the lymph nodes. Different wavelengths of laser energy are often required to remove different colors of pigments, because they absorb different wavelengths of light. Generally, blue and black are the easiest colors to remove. Green, red, and yellow tend to be  the hardest to remove. It may take as many as six to ten laser treatments — with a few weeks of recovery time in between — to remove a tattoo. Some tattoos can never be completely removed.
    ::在去除激光纹身时,高强度激光的脉冲应用于纹身,并被颜料吸收。这把大色素微粒分解成小到能被免疫系统去除的微粒。然后,颜料可能排出体外,或移到身体的其他地区,如淋巴结。激光能量的波长往往需要不同的波长才能去除色素的不同颜色,因为它们吸收了不同的光波长。一般而言,蓝色和黑色是最容易去除的颜色。绿色、红色和黄色往往是最难去除的。可能需要多达6至10次的激光治疗(间隔有几个星期的恢复时间)才能去除纹身。有些纹身永远无法完全去除。

    Why are mehndi designs (like Keith’s trial “henna tattoo”) not permanent? U nlike real tattoos, henna paste is applied on the surface of the skin (shown ), and not injected into the skin with a needle. The dye molecules simply migrate from the paste into the top layer of the epidermis, the stratum corneum.
    ::为什么梅赫迪设计(如基思的试验“Henna纹身 ” ) 不具有永久性呢? 与真正的纹身不同,甲状腺糊被用于皮肤表面(shown ) , 而不是用针注射到皮肤上。 染色分子只是从糊状转移到上层,即直角角。

    Henna paste being applied to create a mehndi design.
    ::使用亨纳糊 来制作一个梅赫迪设计。

    As you have learned, the stratum corneum consists of dead, keratin-filled keratinocytes, which are continually shed and replaced with new cells from the layers below. As a result,  mehndi is not permanent. The design is lost as the cells that contain the dye are shed and replaced.
    ::如你所知, 角膜由死亡的、 填满氯酸盐的乳腺细胞组成, 这些细胞不断被排出, 由下层的新的细胞取而代之。 结果, 甲状腺并不是永久性的。 配染的细胞被排出和替换后, 设计就会丢失 。

    As you read in the beginning of this chapter, mehndi is often applied to the palms of the hands and soles of the feet, which generally results in a darker stain than other areas of the body. This is because the stratum corneum is thicker in these regions, so the dye penetrates through more layers of cells, making the design appear darker. What else is different about the epidermis of the palms and soles? You may recall that these regions are the only place where there is a fifth layer of epidermis — the stratum lucidum — making the skin in these areas even thicker and tougher.
    ::正如你在本章开头所读到的,梅恩迪经常被用于手掌和脚底的掌上,通常造成比身体其他部位更深的污点,这是因为这些区域的角膜较厚,因此染色穿透更多的细胞层,使设计看起来更暗。棕榈和脚底的皮层有别吗?你可能记得,只有这些地区才有第五层的皮层——直角——使这些地区的皮肤更厚、更坚硬。

    Hopefully, Keith thought carefully about the potential emotional and social implications of getting a tattoo — and learned how difficult they are to remove — before getting a real one. Health and safety should also be of utmost concern to anyone considering getting a tattoo. As you have learned in this chapter, the skin acts as a barrier against dangerous pathogens and substances. When you penetrate the skin using a needle, it can introduce harmful viruses and bacteria directly into the dermis, where the blood vessels are. Tattoo artists and shops need to take precautions  to protect their clients against diseases that can be transmitted through blood (such as HIV and hepatitis), as well as bacterial infections. The tattoo artist should wear  disposable gloves and a mask, use  new and unopened needles and ink tubes, and properly sterilize other equipment. Even if the artist takes all the proper precautions, there is still a chance that the unopened ink could have been contaminated with pathogens during the production process. The shop should be aware of any ink recalls. Anyone getting a tattoo should make sure their artist and shop strictly adhere to all local health and safety regulations.
    ::Keith仔细思考了纹身的潜在情感和社会影响 — — 并且知道刺青艺术家和商店需要采取预防措施,保护其客户免受通过血液(如艾滋病毒和肝炎)传播的疾病以及细菌感染。纹身艺术家应佩戴一次性手套和面具,使用新的和未开的针头和墨水管,并适当消毒其他设备。即使艺术家采取了所有适当的预防措施,在生产过程中仍有可能将未开口的墨水沾染入病原体。商店应了解任何内含的记忆。任何获得纹身的艺术家和商店都应确保严格遵守当地卫生和安全条例。

    The risk of disease is not the only risk from tattoos. The pigments in tattoos may contain heavy metals and other potentially toxic substances. According to the U.S. Food and Drug Administration (FDA), many of the pigments used in tattoo inks are industrial-grade, suitable for use in applications such as automobile paints. The FDA is only beginning to study the safety of tattoo inks, and no pigments are currently approved by the FDA for use in tattooing.
    ::纹身的颜料可能含有重金属和其他潜在有毒物质。 据美国食品和药品管理局(FDA)称,纹身墨水中所用的许多颜料是工业级的,适合用于汽车油漆等用途,林业发展局只是开始研究纹身墨的安全性,林业发展局目前没有批准任何颜料用于纹身。

    Additionally, people can sometimes have an allergic reaction to the pigments, or develop scarring or granulomas (small bumps of tissue due to an immune response) around the tattoo. Rarely, people can experience temporary swelling or burning of their tattoos when they get scanned in an MRI machine for a medical procedure. Clearly, people should think carefully about the potential health implications before getting a tattoo.
    ::此外,人们有时会对颜料产生过敏反应,或者在纹身周围产生疤痕或颗粒(免疫反应导致组织小肿块 ) 。 很少有人可以在通过核磁共振机扫描进行医疗程序时经历临时肿胀或烧伤纹身。 显然,人们在纹身之前应该仔细考虑潜在的健康影响。

    Fortunately, Keith found a reputable and safe tattoo artist, and is not experiencing any ill effects from his tattoo. He is happy with his tattoo, at least for now. Tattoos — and other kinds of decoration of the integumentary system — are forms of artistic, personal, and cultural expression that have been used by many cultures over the course of human history. The system that protects us from the elements, helps us maintain homeostasis, and mediates our interactions with the outside world also happens to be easily modifiable! Whether it is a haircut, makeup, beard style, nail polish, or a tattoo, humans have a variety of ways of altering  our integumentary system, which changes our outward appearance and what we communicate to others.
    ::幸运的是,基思找到了一位有声望和安全的纹身艺术家,并且没有受到任何纹身的不良影响。他对纹身感到高兴,至少现在是如此。纹身——以及营养系统的其他装饰品——是人类历史上许多文化一直使用的艺术、个人和文化表达形式。保护我们不受这些元素影响、帮助我们保持顺从和调解我们与外部世界互动的系统也碰巧是容易改变的!无论是发型、化妆、胡子风格、指甲油还是纹身,人类都有各种改变我们外表和我们与他人沟通的外表和内容的方式。

    Chapter Summary
    ::章次摘要

    In this chapter, you learned about the structures and functions of the organs of the integumentary system. Specifically, you learned that:
    ::在本章中,你了解了营养系统各机关的结构和职能。

    • The integumentary system consists of the skin, hair, and nails. Functions of the integumentary system include providing a protective covering for the body, sensing the environment, and helping the body maintain homeostasis.
      ::内脏系统由皮肤、毛发和钉子组成,内脏系统的职能包括:为身体提供防护,感测环境,帮助身体保持自足。
    • The skin’s main functions include preventing water loss from the body, serving as a barrier to the entry of microorganisms, synthesizing vitamin D, blocking UV light, and helping to regulate body temperature.
      ::皮肤的主要功能包括防止身体缺水、阻止微生物进入、合成维生素D、堵住紫外线灯和帮助调节体温。
    • The skin consists of two distinct layers: a thinner outer layer called the epidermis, and a thicker inner layer called the dermis.
      ::皮肤由两层不同的层组成:一层较薄的外层,称为皮层,另一层较厚的内层,称为皮层。
      • The epidermis consists mainly of epithelial cells called keratinocytes, which produce keratin. New keratinocytes form at the bottom of the epidermis. They become filled with keratin and die as they move upward toward the surface of the skin, where they form a protective, waterproof layer.
        ::上皮细胞主要包括称为乳腺细胞的上皮细胞,它们产生氯酸盐,在皮皮底部形成新的乳腺细胞,在皮肤上向皮肤表面移动时被填满并死亡,它们形成一个保护性、防水的层。
      • The dermis consists mainly of tough connective tissues that provide strength and stretch, as well as almost all skin structures, including blood vessels, sensory receptors, hair follicles, and oil and sweat glands.
        ::皮肤主要包括提供强度和伸展力的硬性连接组织,以及几乎所有皮肤结构,包括血管、感官受体、毛囊、油和汗腺。

      ::皮皮质细胞主要包括皮上细胞,叫做乳腺细胞,它们产生氯丁酸;在皮皮底部形成新的乳腺细胞;在皮肤表面向上移动时,它们充满氯丁酸并死亡,它们形成保护性、防水的一层;皮皮质主要是提供强度和伸展力的硬结组织,以及几乎所有皮肤结构,包括血管、感官感应器、毛囊、油和汗腺。
    • Cell types in the epidermis include keratinocytes (which make up 90 percent of epidermal cells), melanocytes that produce melanin, Langerhans cells that fight pathogens in the skin, and Merkel cells that respond to light touch.
      ::上皮细胞类型包括乳腺细胞(占上皮细胞的90%)、生产梅林的黑素细胞、与皮肤病原体抗争的兰根细胞和与轻触反应的默克尔细胞。
    • In most parts of the body, the epidermis consists of four distinct layers. A fifth layer occurs only in the epidermis of the palms of the hands and soles of the feet.
      ::在身体的大多数部位,皮层由四个不同的层组成,第五层只出现在手掌和脚底掌掌的皮层上。
      • The innermost layer of the epidermis is the stratum basale, which contains stem cells that divide to form new keratinocytes. The next layer is the stratum spinosum, which is the thickest layer, and contains Langerhans cells and spiny keratinocytes. This is followed by the stratum granulosum, in which keratinocytes are filling with keratin and beginning  to die. The stratum lucidum is next, but only on the palms and soles. It consists of translucent dead keratinocytes. The outermost layer is the stratum corneum, which consists of flat, dead, tightly packed keratinocytes that form a tough, waterproof barrier for the rest of the epidermis.
        ::上皮细胞最深层的一层是直肠直肠,其中含有分解形成新乳腺细胞的干细胞。下一层是最厚层的直肠脊柱,其中含有兰汉斯细胞和脊椎脊椎细胞。接下来是直肠颗粒,其中脊髓细胞填满了氯拉丁并开始死亡。直肠直肠直肠直肠直肠直肠直肠直肠直肠直肠直肠直肠直肠直肠直肠。它由半透明死亡的脊椎细胞组成。最外层是直肠角,由平坦、死寂、紧凑的脊椎细胞组成,形成一个坚硬的、防水的外皮细胞屏障。

      ::上皮细胞最深层的一层是直肠直肠,其中含有分解形成新乳腺细胞的干细胞。下一层是最厚层的直肠脊柱,其中含有兰汉斯细胞和脊椎脊椎细胞。接下来是直肠颗粒,其中脊髓细胞填满了氯拉丁并开始死亡。直肠直肠直肠直肠直肠直肠直肠直肠直肠直肠直肠直肠直肠直肠直肠。它由半透明死亡的脊椎细胞组成。最外层是直肠角,由平坦、死寂、紧凑的脊椎细胞组成,形成一个坚硬的、防水的外皮细胞屏障。
    • The  epidermis protects  underlying tissues from physical damage and pathogens. Melanin in the epidermis absorbs and protects underlying tissues from UV light. The epidermis also prevents loss of water from the body and synthesizes vitamin D.
      ::皮层皮层保护底部组织免受身体损害和病原体的伤害。皮层皮下皮革中的梅兰宁吸收并保护底部组织免受紫外线照射。皮层皮下皮也防止身体水的流失,并合成维生素D。
      • Melanin is the main pigment that determines the color of human skin. However, the pigments carotene and hemoglobin also contribute to skin color, especially in skin with low levels of melanin.
        ::美兰素是决定人类皮肤颜色的主要色素,但是,色素胡萝卜和血红蛋白也助长肤色,特别是低米兰素皮质的肤色。
      • The surface of healthy skin normally is covered by vast numbers of bacteria representing about one thousand species from 19 phyla. Different areas of the body provide diverse habitats for skin microorganisms. Usually, microorganisms on the skin keep each other in check unless their balance is disturbed.
        ::健康的皮肤表面通常包含大量细菌,代表19个植物群的大约1 000种物种,身体的不同区域为皮肤微生物提供了不同的栖息地,通常皮肤上的微生物相互调节,除非它们的平衡受到干扰。

      ::Melanin是决定人类皮肤颜色的主要色素,然而,色素颈动脉和血红蛋白也助长肤色,特别是低度梅兰宁皮肤的肤色,健康皮肤表面通常包含大量细菌,代表19种植物的大约1 000种,身体的不同区域为皮肤微生物提供了不同的栖息地,通常皮肤上的微生物会相互调节,除非它们的平衡受到干扰。
    • The thicker inner layer of the skin — the dermis — has two layers. The upper papillary layer has papillae extending upward into the epidermis and loose connective tissues. The lower reticular layer has denser connective tissues and structures, such as glands and hair follicles. Glands in the dermis include eccrine and apocrine sweat glands, as well as sebaceous glands. Hair follicles are structures where hairs originate.
      ::较厚的皮肤内层——皮肤皮层——有两层,上毛细皮层向上延伸至上皮毛和松散的接合组织,下视线层有较稠密的连接组织和结构,如腺和毛囊,皮层的腺包括羊水和羊水、羊水、羊水、羊毛、毛发结构。
    • Functions of the dermis include cushioning subcutaneous tissues, regulating body temperature, sensing the environment, and excreting wastes. The dense connective tissues of the dermis provide cushioning. The dermis regulates body temperature mainly by sweating and by vasodilation or vasoconstriction. The many tactile sensory receptors in the dermis make it the main organ for the sense of touch. Wastes excreted in sweat include excess water, electrolytes, and certain metabolic wastes.
      ::皮肤的功能包括衬垫下皮组织、调节体温、感知环境和排泄废物。皮肤的稠密连接组织提供衬垫。皮肤主要通过汗水和血管变异或血管收缩调节身体温度。皮肤中许多触感受体使它成为触感的主要器官。汗水中排出的废物包括多余的水、电解剂和某些代谢废物。
    • Hair is a filament that grows from a hair follicle in the dermis of the skin. It consists mainly of tightly packed, dead keratinocytes that are filled with keratin. The human body is almost completely covered with hair follicles.
      ::毛发是一种丝状纤维,从皮肤皮肤皮质的毛发囊中长出来,主要由紧凑的死乳腺细胞组成,里面装满了氯酸盐,人体几乎完全被毛发囊覆盖。
    • Hair helps prevent heat loss from the head and protects its skin from UV light. Hair in the nose filters incoming air, and the eyelashes and eyebrows keep harmful substances out of the eyes. Hair all over the body provides tactile sensory input. The eyebrows also play a role in nonverbal communication.
      ::毛发有助于防止头部发热,保护皮肤免受紫外线光照射。鼻腔过滤器的毛发进入空气,眼睫毛和眉毛使有害物质远离眼睛。全身的毛毛提供触觉感官输入。眉毛在非语言交流中也有作用。
    • The part of a hair that is within the follicle is the hair root. This is the only living part of a hair. The part of a hair that is visible above the skin surface is the hair shaft. It consists of dead cells.
      ::毛发在毛发囊中的部分是毛根。 这是毛发中唯一活的部分。 在皮肤表面上方可见的毛发部分是毛管, 它由死细胞组成 。
      • Hair growth begins inside a follicle when stem cells within the follicle divide to produce new keratinocytes.
        ::毛发生长开始于一个卵囊内部 当在卵囊分裂中的干细胞 产生新的乳腺细胞时
      • A hair shaft has three zones: the outermost zone called the cuticle, the middle zone called the cortex, and the innermost zone called the medulla.
        ::毛发管有三个区域:最外边称为切片区,中间带称为皮层区,最内边称为中层。

      ::毛发生长开始于卵蛋中,在卵蛋分块内的干细胞产生新的心肌细胞。 毛发轴有三个区域:最外边称为切片区,中间带称为皮层区,而内边称为中层区。
    • Genetically controlled, visible characteristics of hair include hair color, hair texture, and the extent of balding in adult males. Melanin (eumelanin and/or pheomelanin) is the pigment that gives hair its color. Aspects of hair texture include curl pattern, thickness, and consistency.
      ::毛发的遗传、可见特征包括毛发颜色、毛质和成年男性秃头的程度。梅拉宁(eumelainin和/或phemelainin)是发色的色素。毛质的各个方面包括卷发、厚度和一致性。
    • Among mammals, humans are nearly unique in having undergone significant loss of body hair during their evolution, probably because sweat evaporates more quickly from less hairy skin. Curly hair also is thought to have evolved at some point during human evolution, perhaps because it provided better protection from UV light.
      ::在哺乳动物中,人类在进化过程中出现大量毛发流失,这几乎是独一无二的,原因可能是汗水从毛皮较少的皮肤中蒸发得更快。 卷发也被认为在人类进化过程中的某个时刻有所演变,或许是因为它提供了更好的保护,使其免受紫外光的影响。
    • Hair has social significance for human beings, being an indicator of biological sex, age, and ethnic ancestry. Human hair also has cultural significance. For example, hairstyle may be an indicator of social group membership.
      ::头发对人类具有社会意义,是生物性别、年龄和民族血统的一个指标,人的头发也具有文化意义,例如发型可能是社会群体成员的一个指标。
    • Nails consist of sheets of dead, keratin-filled keratinocytes. The keratin in nails makes them hard but flexible. They help protect the ends of the fingers and toes, enhance the sense of touch in the fingertips, and may be used as tools.
      ::钉子由死尸的床单组成。 钉子中的氯酸盐使得它们硬而灵活。 它们有助于保护手指和脚趾的端端,增强指尖的触摸感,并且可以用作工具。
    • A nail has three main parts: the nail root, which is under the epidermis; the nail plate, which is the visible part of the nail; and the free margin, which is the distal edge of the nail. Other structures under or around a nail include the nail bed, cuticle, and nail fold.
      ::钉子有三个主要部分:指甲根(指甲根,指甲底部);指甲板(指甲的可见部分);自由边缘(指甲的侧边 ) 。 指甲下或周围的其他结构包括指甲床、指甲和钉子折叠。
    • A nail grows from a deep layer of living epidermal tissues, called the nail matrix, at the proximal end of the nail. Stem cells in the nail matrix keep dividing to allow nail growth, forming first the nail root and then the nail plate as the nail continues to grow longer and emerges from the epidermis.
      ::指甲从指甲最接近尾端的称为指甲基体的深层活的上皮组织层中生长而来。 指甲基体中的尖细胞保持分裂,以允许指甲生长,首先形成指甲根,然后作为指甲继续长长,从指甲底部显现出来。
    • Fingernails grow faster than toenails. Actual rates of growth depend on many factors, such as age, sex, and season.
      ::实际增长率取决于许多因素,如年龄、性别和季节。
    • The color of the nail bed can be used to quickly assess oxygen and blood flow in a patient. How the nail plate grows out can reflect recent health problems, such as illness or nutrient deficiency. Nails — and especially toenails — are prone to fungus infections. Nails are more permeable than skin and can absorb several harmful substances, such as herbicides.
      ::指甲床的颜色可以用来快速评估病人的氧气和血液流,指甲板的生长方式可以反映最近的健康问题,例如疾病或营养缺乏症,指甲——特别是脚趾甲——容易感染真菌,指甲比皮肤更容易渗透,可以吸收几种有害物质,例如除草剂。
    • Skin cancer is a disease in which skin cells grow out of control. It is caused mainly by excessive exposure to UV light, which damages DNA. Skin cancer affects more Americans than all other cancers combined.
      ::皮肤癌是一种皮肤细胞发育失控的疾病,主要是过度接触紫外线光造成的,它损害DNA。 皮肤癌对美国人的影响大于所有其他癌症的总和。
    • There are three common types of skin cancer: basal cell carcinoma, squamous cell carcinoma, and melanoma. Carcinomas are more common and unlikely to metastasize. Melanoma is rare and likely to metastasize. It causes most skin cancer deaths.
      ::皮肤癌有三种常见类型:巴萨尔细胞癌、肮脏细胞癌和黑瘤;癌瘤更常见,不太可能转移;梅兰诺瘤很少,而且可能转移;导致大多数皮肤癌死亡。
    • Besides exposure to UV light, risk factors for skin cancer include having light colored skin, having many moles, and a family history of skin cancer, among several others.
      ::除了接触紫外光外,皮肤癌的风险因素还包括皮肤浅色、多颗摩尔和家族皮肤癌史等。

    Now that you have learned about the organs on surface of the body, read the next chapter to travel inside and learn about the skeletal system, which protects and supports us internally, among other functions.  
    ::现在你已经了解了身体表面的器官, 读下一章 进入内部旅行,了解骨骼系统, 骨骼系统在内部保护和支持我们, 以及其他功能。

    Chapter Summary Review
    ::" 概述 " 章次

    1. Describe one way in which the integumentary system works with another organ system to carry out a particular function.
    ::1. 说明编组系统与另一机关系统合作履行特定职能的一种方式。

    2. Put the following layers of skin in order, from the deepest layer to the layer closest to the surface:
    ::2. 从最深层至最接近表面的层排列以下皮肤层的顺序:

    papillary layer; stratum basale; reticular layer; stratum spinosum
    ::毛细层; 直流巴萨; 直流层; 直流脊柱

    3. The basement membrane is between the __________________.
    ::3. 地下室膜介于______________之间。

    a. dermis and epidermis
    ::a. 皮肤和皮皮

    b. dermis and the subcutaneous tissues beneath it
    ::b. 皮肤和下面的皮下组织

    c. dermis and the hair in the follicle
    ::c. 皮肤和毛发

    d. nail matrix and the nail bed
    ::d. 指甲矩阵和指甲床

    4. For each of the descriptions below, match it to the protein best described by it.
    ::4. 以下每种描述都与它所描述的最佳蛋白质相匹配。

    keratin; collagen; melanin; elastin
    ::keratin; collagen; 米拉宁; 弹性体

    a. helps provide strength and elasticity in the lower layer of the dermis
    ::a. 帮助提供皮肤下层的强度和弹性

    b. makes up the loosely arranged fibers in the upper layer of the dermis
    ::b. 构成皮肤上层松散安排的纤维

    c. the predominant protein in hair, skin, and nails
    ::c. 毛发、皮肤和指甲中占主导地位的蛋白质

    d. protects against damage from UV light.
    ::d. 防止受到紫外线光线的损害。

    5. Keratinocytes are found in __________________. 
    ::5. 甲状腺细胞在______________________________中。

    a. skin
    ::a. 皮肤

    b. hair
    ::b. 头发

    c. nails
    ::c. 指甲

    d. all of the above
    ::d. 以上所有情况

    6. Papillae extend ____________________. 
    ::6. Papillae 扩展 ___________________________________________________________________________________________________________________________________________________________________________________

    a. from the sebaceous glands to the surface of the skin
    ::a. 从迭生的腺到皮肤表面。

    b. from the sweat glands to the surface of the skin
    ::b. 从汗腺到皮肤表面

    c. from the epidermis down into the dermis
    ::c. 从皮层到皮层

    f. from the dermis up into the epidermis
    ::f. 从皮革到皮革

    7. Describe two types of waterproofing used in the integumentary system. Include the types of molecules and where they are located.
    ::7. 描述在编织系统中使用的两种防水方法,包括分子的类型和位置。

    8. Explain why nails enhance touch sensations.
    ::8. 解释为什么指甲会增加触摸感。

    9. Why do you think light colored skin is a risk factor for skin cancer?
    ::9. 为什么你认为浅色皮肤是皮肤癌的风险因素?

    10. Which vitamin is synthesized by the skin?
    ::10. 皮肤合成哪一种维生素?

    a. vitamin A
    ::a. 维生素A

    b. vitamin D
    ::b. 维生素D

    c. vitamin B9
    ::c. 维生素B9

    d. vitamin E
    ::d. 维生素E

    11. Describe the similarities between how the epidermis, hair, and nails all grow.
    ::11. 描述下皮、头发和钉子是如何生长的相似之处。

    12. True or False:  The inside of the mouth is considered epidermal tissue.
    ::12. 真实或假:口内被认为是上皮组织。

    13. True or False:  Epidermal cells are filled with an increasing amount of keratin as they go from the lowest layer to the outermost layer.
    ::13. 真实的或假的:在从最低层到最外层的中间细胞中,填充的氯丁二烯含量不断增加。

    14. True or False:  Cells in the stratum corneum of the skin do not have a nucleus or organelles.
    ::14. 真实或假:皮肤直角的细胞没有核或风琴。

    15. What does the whitish crescent-shaped area at the base of your nails (toward your hands) represent? What is its function?
    ::15. 指甲底部的Whattish新月形区域(手顶)代表什么?其功能是什么?

    16. What is one difference between human hair and the hair of non-human primates?
    ::16. 人的头发与非人类灵长类动物的头发有什么区别?

    17. Approximately how long does it take new keratinocytes at the lowest level of the epidermis to reach the surface of the epidermis?
    ::17. 大约需要多久才能达到皮层表面? 大约需要多久才能达到皮层最低层的新的乳腺细胞?

    a. 1.5 days
    ::a. 1.5天

    b. 1.5 weeks
    ::b. 1.5周

    c. 1.5 months
    ::c. 1.5个月

    d. 1.5 years
    ::d. 1.5年

    18. True or False:  Blood vessels extend through the entire thickness of the skin.
    ::18. 真实或假:血筒穿透整个皮肤厚度。

    19. True or False:  Cells that produce melanin are located in the dermis of the skin.
    ::19. 真实的或假的:生产梅拉宁的细胞位于皮肤的皮肤皮下。

    20. Describe the relationship between skin and hair.
    ::20. 描述皮肤和头发之间的关系。

    21. What kind of skin cancer is a cancer of a type of stem cell?
    ::21. 何种皮肤癌是某种干细胞的癌症?

    22. For the skin and hair, describe one way in which they each protect the body against pathogens.
    ::22. 对于皮肤和头发,请说明它们各自保护身体免受病原体伤害的一种方式。

    23. If sweat glands are in the dermis, how is sweat released to the surface of the body?
    ::23. 如果汗腺在皮肤中,如何将汗水释放到身体表面?

    24. Explain why you think that physicians usually insist that patients remove any nail polish before having surgery.
    ::24. 解释一下为什么你认为医生通常坚持要求病人在手术前切除指甲油。

    25. True or False:  Langerhans cells are immune cells located in the epidermis.
    ::25. 真实或假:Langerhans细胞是位于皮层的免疫细胞。

    26. True or False:  Fingerprints happen because of  structures on the surface of the epidermis.
    ::26. 真实的或假的:指纹是因上皮层结构造成的。

    27. Describe generally how the brain gets touch information from the skin.
    ::27. 一般描述大脑如何从皮肤获得触摸信息。