Bio Now Characteristics of Life Notes

Characteristics of Life Part I: Pre-Video Questions 1) Provide a brief definition of the following terms to gain familiarity before watching the video. a. Biology: the branch of science that is concerned with the study of life and living organisms b. Cell: The smallest unit of life that displays all the properties of life; composed of cytoplasm surrounded by a plasma membrane c. Organ system: group of related organs working together d. Energy: the capacity to do work and bring about change e. Metabolism: the sum of all the chemical reactions that occur in a cell f. Photosynthesis: process, usually occurring in chloroplasts, that uses solar energy to reduce carbon dioxide to carbohydrate g. Autotroph: organism that can capture energy *plants* and synthesize organic molecules from inorganic nutrients h. Heterotroph: organisms that cannot synthesize needed organic compounds from inorganic substances and therefore must take in organic food i. Homeostasis: maintenance of normal internal conditions in an organism or cell by means of self- j. Enzyme: organic catalyst, usually a protein, that speeds up a reaction in cells due to its particular regulation mechanisms shape k. Stimuli: a detectable change in the internal or external environment l. Reproduce: the process of creating a new individual of the same kind m. Adaptation: species modification in structure, function, or behavior that makes a species more susceptible to its environment n. Evolution: genetic change in a species over time, resulting in the development of genetic phenotypic differences that are the basis of natural selection; descent of organisms from a common ancestor Biology is the study of life, but what is life? Is there a simple definition to define what is living and what is nonliving? When looking at something, you can probably clearly tell if it is alive or not. But, can you clearly explain why you know that? Truthfully, there is not a simple definition. Instead, living organisms are defined by certain characteristics they all share. Thinking of bacteria, a mushroom, a squirrel, and yourself, what are characteristics you all share? For example, are you all living because you move or because you change? When an organism is displaying each characteristic, it is alive. If it is not, then the organism is in serious trouble or it is not a living organism at all. The characteristics of life encompass everything that makes a living organism “alive”. Everything studied in biology can be related back to these common characteristics. However, since you are probably just beginning to learn about biology, they may be difficult to understand. This video will show an example of an organism meeting and not meeting each characteristic, or a “winner” and a “loser,” to give a clear example you can relate to for the rest of your biology course. 2) What characteristics do you think define a living organism? The book states that the characteristics that define a living organism are: - Organization - Requires materials and energy - The ability to reproduce and develop - Responds to stimuli - Homeostatic - Able to adapt to their environment 3) If a once living organism is no longer alive, would you call it dead or non-living? The difference between dead and non-living organisms is something that is dead was once living and something that is non-living was never alive in the first place. An organism that is no longer alive would be considered dead. 4) What does your body do each day to stay alive? There are so many things that my body does each day automatically to keep me alive. Breathing, pumping blood, digesting food, and maintain a constant body temperature. Part II: Video Questions 5) What is the difference between reproduction and development? The difference between reproduction and development is reproduction is when the new individual of the same species is formed, and development is what happens beginning after the zygote of the organism is formed. 6) Does an organism have to reproduce to stay alive? Each individual organism does not have to reproduce to stay alive, but some members of the species must reproduce in order of the species to survive. 7) Do eggs from the store represent unsuccessful reproduction and development? Eggs from the store represent unsuccessful reproduction 8) Describe each level of organization in a living organism. Atom: smallest particle of an element that displays the properties of the element Molecule: Union of two or more atoms of the same element; also, the smallest part of a compound that retains the properties of the compound. Cell: the smallest unit of life that displays all the properties of life; composed of cytoplasm surrounded by a plasma membrane. Tissue: group of similar cells combined to perform a common function Organ: combination of two or more different tissues performing a common function. Organ System: group of related organs working together. 9) What is an emergent property? Smaller parts combine to make increasingly complex systems (heart cells and properties make up the heart, making it pump) 10) How does energy from the sun reach all living organisms? Nearly everything eats sunshine – or eats something else that ate sunshine. The Sun is the major source of energy for organisms and the ecosystems of which they are a part. Producers, such as plants and algae, use energy from sunlight to make food energy by combining carbon dioxide and water to form organic matter. 11) What is the difference between an autotroph and a heterotroph? A heterotroph needs to take in organic food and an autotroph can synthesize inorganic nutrients 12) Why is a wood tick called a parasite? A tick is considered a parasite because it lives by feeding off of other organisms. 13) What stimuli does an organism respond to in its environment? To the external stimuli 14) Why is movement not a characteristic of life? Because not all living organisms move, but they are still alive shown in other ways 15) Describe several internal and external ways an organism responds to the environment. A lizard is cold so it lies in the sun; plants lean towards sunlight; your body sweats when it is overheated 16) During homeostasis, what physiological factors need to be balanced within a living organism? Internal temperature, blood sugar levels 17) Describe an example of your body maintaining homeostasis. Your liver releases sugar throughout the day if you forget to eat in order to maintain your blood sugar levels 18) How is homeostasis controlled in a living organism? Homeostasis is controlled by one or more tissues themselves or the nervous system. 19) What is genetic modification? When an organism is genetically engineered to have a desired result. IE in the video corn was genetically modified to be resistant to the herbicide. 20) Why is it necessary for organisms to have the ability to adapt? If they do not adapt to a changing environment, then they will eventually die off. 21) Why is the current environment making it difficult for organisms to adapt? Lack of resources due to the fact that their environment are changing so rapidly with deforestation and destroying of wildlife. 22) How do organisms develop adaptations? When environments change, organisms sometimes poses traits that make them better suited to the environment. Part III: Video Evaluation 23) Would the observations in this video be classified as a scientific experiment? Would this be considered science? Yes, there was an observation made and an experiment conducted. IE dead grass under wheelbarrow 24) Were the losers shown in the video only losing at one characteristic? They were all dead. 25) Is every other characteristic shown the result of adaptation? It is possible