{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

midterm1 BIS 10

midterm1 BIS 10 - 1 Overview I draw from your textbook the...

Info icon This preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
1. Overview I draw from your textbook the following list of characteristics or attributes of life.  Collectively, they provide a working definition of life: Order Metabolism Adaptations Responsiveness/homeostasis Reproduction Genes Evolution Order.   The order of natural systems  ( e. g.,  the universe itself) decreases. Entropy  is the name given to this decrease in order. Energy is required to produce order and to  maintain it. Within a system energy may be drawn from one part to increase orderliness  ( i.e ., decrease entropy) in another part. A living organism draws energy from the  environment to establish and to maintain orderliness. This may be close to a general  definition of life. Metabolism.   Organisms orchestrate sequences of stepwise chemical changes  which provide energy and the chemicals that are building blocks for making more  organism. We call these chemical sequences metabolism. Photosynthesis, respiration, and  fermentation are metabolic processes by means of which an organism obtains the energy  necessary to establish and maintain order.  Adaptations.   An organism has particular features that adapt it to its environment.  Examples of adaptations range from the color of frogs to the ability of fungi to "eat"  cellulose to the astounding ability of some micro-organisms to grow in acid hot springs, a  lethal environment for all other organisms. Responsiveness  is a broad (and vague) biological concept. An organism senses a  change in its environment and responds to that change. If the response counteracts the  change, it is called homeostasis . A familiar example of homeostasis is the regulation of  body temperature of mammals and birds. Environmental change to which an organism  responds is called a stimulus . The structure that detects that stimulus and triggers the  response is called a receptor . Reproduction.   Since death is the ultimate fate of any organism, the persistence of  a population requires reproduction. While individuals are born and die, life in a 
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
population (at least until its extinction) is continuous. The political and ethical debate  about when human life begins seems to me to ignore this continuity of life. Genes.   Offspring resemble their parents. The machinery responsible for the  resemblance are the genes . As you know, genes are the chemical blueprints that specify  an organism by specifying its parts and their assembly. Deoxyribonucleic acid, better  known as DNA, contains those blueprints in its linear sequence of purine and pyrimidine  bases.
Image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern