Study Guides (248,075)
United States (123,277)
Biology (180)
BIOL 240W (7)
Dr.Love (1)

Exam 1 study guide - Chapter 40, 46, 35, 39, 47

6 Pages
Unlock Document


Short answer: (1-3 pages each question) 1. Explain the difference between animals that are regulators and those that are conformers. Give 2 examples Feedback control is how animals manage their internal environment when they are exposed to certain environments. Regulator animals use its internal mechanisms to control the internal change of its body when they are exposed to the fluctuated temperatures of the environment. With that being said, animals that are regulator would keep their temperature relative the same and independently across the wide range of the environment temperature. On the other hand, conformer animals are animals that allow their internal condition to change with certain environment. One example of a regulator is a Ruby - throated hummingbird. The hummingbirds as they fly to the north, for example, central Florida to avoid the winter seasons.As they fly from a cold place to a mild temperature habitat, even the environment temperatures are fluctuated, the hummingbirds body temperature don’t change, or if it changes, only a one or two degree Celsius.Another example is a river otter, which as it moves from one river to another, although the temperature of these rivers may fluctuate, their body temperature would stay the same or increase just one or two degree Celsius. An example of a conformer is spider crabs. These crabs allow their internal temperature to conform to their ocean environment. Many invertebrates are conformers. Another example is the starfish.As they live in the ocean, their body temperature is low as the ocean’s cool. But as they live in the sand, they absorb heat from the sun, and their body temperature increases. Homeostasis is the way to maintenance the internal balance, which largely relies on negative feedback. For example, when a conformer animal goes from a hot area to a cooler area, their control center send out a stimulus tells them that their body needs heat to a particular set point, in this case is the conformer body temperature. The heat would then produce to warm up their body. Similarly, after a long mile run, our body increases due to the heat produced and we experience sweating.As we sweat, our moisture evaporates which cools our body down and eventually set the body temperature back to set point. 2. Explain the four processes by which heat is exchanged with the environment 4 processes in which heat is exchanged with the environment are radiation, evaporation, convection and conduction.As known, heat is always flow from high temperature to lower temperature. Conduction is a direct transfer of heat by thermal motion. Evaporation is the process of losing heat as a liquid converted to a gas.As the air or water molecule move past a surface, said a pond, heat is losing and that is called convection. Radiation is a form of heat loss from one object to another without physically contact. Conduction is the heat lost from an organism to its environment through a thermal direct transfer. For example, when we first jump on to the treadmill during winter time and touch the handles of the treadmill, we feel the sudden cold. That is because the heat from our body transfer to that cold treadmill handles. Evaporation is a heat loss from the surface of a liquid or air. For instance, you have an outdoor pool and during a summer time, the temperature on a surface of the water is too hot and need to cool down. Water on the pool would evaporate and the heat is said to be lost. Convection is heat loss to the air or liquid from a surface. For example, after exercise too much and we feel hot that we want to cool off ourselves immediately; therefore we turn on a fan or an air conditioner.As the airflow over our skin, we feel a breeze which contributes to heat loss to the environment. Radiation is when a heat loss through distance. For example, as we driving we can feel the radiated heat from the mirror that absorb from the sun. We absorb that heat radiating and in return emit a smaller amount of energy to the surrounding air. 3. Describe the mechanism of homeostasis and give an example of negative and positive feedback The mechanisms of homeostasis are regulation of blood pressure, regulation of pH and regulation of blood glucose levels. One mechanism of homeostasis is the regulation of blood glucose levels. We each have a certain set point, which is a particular value, in this case is a certain amount of sugar need in our body for us to function properly.After each meal, our blood glucose level goes up depending on how much food that we eat. Insulin would then come and stimulate glucose out of the blood and put that into the cell as storage, or glycogen. This is an example of a negative feedback. As we don’t eat breakfast in the morning may be because we forget or because we are late, after few hours, our blood glucose level drops and we may faint. To get this back to a set point, a control center generates output that triggers a response, and glucagon would be secretes to break down glycogen, which is the stored glucose and release that glucose into the blood so that the blood level can be back to a set point. This is an example of positive feedback. Although as the blood sugar drops and we may take candies or something gluten to eat, it would take couple minutes for the glucose to be back to a set point.And if we skip breakfast too often, our homeostasis is altered and would keep altered until it reset to the set point, which means until we eat proper breakfast every morning. 4. Plant have an immune system is a bit shocking. Explain? Surprisingly, plants like most animals have organs and an immune system. Cells made up tissues which then made organs or organ system. There are 3 types of tissues: dermal, ground, and vascular. Dermal tissues are called epidermis, which discover by cuticle, their job is to prevent water loss. Vascular, also called stele, they carry out long- distance transport of materials between the roots and shoot systems. Within the stele tissue is a complex conducting tissue that consist primarily of the xylem and phloem. Xylem conducts water and dissolved minerals upward from roots into the shoots. Phloem transport sugars and food product from the leaves to where they are needed, usually roots and developing leaves or fruits. The ground tissue, which support and give thickness to stem and root, has specialized cells that can function in multiple things from storage, photosynthesis to support. Plants don’t have complex organs that each organ does their own job as in animals. Therefore when their immune system gets affected by biotic and abiotic factors, plants must defense back by their cell walls, epidermis, etc. These substances besides providing protection for the plants they also give the plants rigidity and thick, stronger. Plants’interaction with the environment often bring beneficial or harmful to them and in the environment where plants are easily infected by pathogens and herbivores, plants use their defense systems to deter herbivores and combat pathogens. In any environment, the plants faced stress
More Less

Related notes for BIOL 240W

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.