Bio lecture 4

Some species of single-celled organisms live in hot springs where the temperatures are close to boiling. Other single-celled organisms live in ice. Do you think that the internal temperature ranges each of these species must maintain to survive are the same? Why or why not?

Homeostasis is a dynamic process and internal conditions are no held constant. Homeostasis mechanisms constantly adjust internal conditions because external conditions are widely variable

Write your own description/explanation of homeostasis.

Homeostasis is the ability for an organism to keep internal conditions within a specific range and is required for proper functioning of all organisms internal conditions such as blood sugar level, body temperature, etc......Stability with variability

How are plant & animal homeostatic mechanisms different?

Homeostatic mechanisms of plants & animals respond to different stimuli in specific & different ways-Plants = stationary, but have very flexible growth patterns. Photosynthesis, stomata, Indeterminate growth, apical dominance, photoperiodism, gravitropism, drought stress, etc.-Animals = can move; have a central control system (nervous system). Determinate growth.

Explain why maintaining homeostasis is essential for all organisms.

It is required for proper functioning of internal conditions like blood sugar level, body temperature, etc which if move out of range can cause organism to not be able to function

A study reported that people who use cell phones one or more times per week for 10 or more years have a statistically significantly greater chance of developing a specific type of ear tumor called acoustic neuroma. Can you state from these results that regular cell phone use causes acoustic neuroma?

No association and causation are different. NO, because correlation is not the same as causation. Alternative hypotheses are possible - other characteristics could be different b/n cell phone users and non-users.

Which of the following, if any, correctly compares determinant and indeterminate growth? Determinate growth is observed in the early stages of a plant's life; indeterminate growth is observed in adult plants. The shoot systems of plants show indeterminate growth; the root systems show determinate growth. Indeterminate growth is growth that occurs at the tips of plants' roots and shoots; lateral buds grow via determinate growth. Plants only show determinate growth; animals only show indeterminate growth. None of the above

None of the Above Mastering Bio Input: Many parts of plants (e.g. shoots, roots) are capable of indeterminate growth throughout the life of a plant. The ability to grow in various ways throughout their lives is beneficial for plants since they cannot move to change their surrounding conditions. Certain plant parts such as flowers show determinate growth - they have a fixed plan (e.g. six oval petals in a particular arrangement) and stop growing once they've developed to a specific point. Provide Feedback

Describe the function of vascular tissue.

vascular tissue: Its a tubing system that goes throughout a plant and allows transport of water, nutrients, signaling molecules, and other types of molecules Vascular tissue allows for the movement of cells and fluids throughout the plan functioning similar to blood systems in the human body.

Why is indeterminate growth beneficial for plants? Explain why indeterminate growth is less important for animals.

indeterminate growth is open ended growth that can be lifelong (e.g. plant shoots and roots); indeterminate growth allows stationary organisms to respond to environmental changes throughout their life time (change in direction of sunlight) indeterminate growth is less important for animals because they have mobility; can change their environment and escape threats while plants are stationary. Indeterminate growth is important to respond to outside stimuli such as competition or changes in sunlight availability. Indeterminate growth is not important because they stop growing when a certain point in development is reached and do not have the same problems as plants do.

Where does growth occur on plants?

length wise growth occurs only at tips of shoots and roots

Explain why, if you put a nail in the trunk of a tree, the height of the nail above the ground won't change even as the tree gets taller.

length-wise growth occurs only at topes of shoots and roots and does not expand in center of plant Growth occurs at the very bottom in the root tips and at the very top of the tree and not in the center so the sign will stay at the same place.

Explain how plants obtain the water, light energy, and carbon dioxide required for photosynthesis, the process by which plants generate food (carbohydrates) using the energy of light.

plants obtain carbon dioxide from stomata, water from roots , and light energy from chloroplasts in stomata cells. Leaves absorb light energy-Stomata (leaf pores) allow carbon dioxide (CO2) in & water (H2O) out.-Roots absorb water & nutrients.-Carbohydrates = stored energy.-Generates oxygen as a byproduct. Light energy comes from the sun and the water comes from the roots. The sun energy and carbon dioxide are absorbed and converted to glucose and create a carbohydrate that the plant stores. This will function as the food.

Which of the following, if any, correctly describe(s) plant structure and growth? A. Stomata are important for allowing a plant to obtain water.' B. Molecules travel throughout a plant via fluid in the vascular tissue. C. Length-wise growth occurs along the entire surface of roots and shoots. D. All of the above E. None of the above

B: Molecules travel throughout a plant via fluid in the vascular tissue.

What are the four basic features of all homeostatic mechanisms? Using the four basic features of all homeostatic mechanisms, describe in general terms how your body would respond to an increase in blood sugar after you eat a candy bar

The four basic homeostatic mechanisms are sensing change in specific internal and external condition through stimuli; communicate messages throughout organism; interpret messages and integrate multiple messages to determine appropriate response; and cause appropriate response if necessary Our bodies would sense the change in blood sugar. The communication would be carried out throughout our bodies, and the message would be interpreted to convert it to energy and integrate the hormones being moved. Finally, the appropriate response by our bodies to respond to the increase of blood sugar by making us hyper. Lecture: the first thing that needs to happen is that the organism needs to sense the condition, so for example eating the candy bar your body would have to detect an increase in blood sugar. You can only regulate something your body can detect, which is that changing condition. The sensors that detect the increase of blood sugar need to communicate that message throughout the organism. Then the message needs to be received and interpreted in the body. Finally the body responds to the increase of blood sugar that goes beyond the range by decreasing your blood sugar with appropriate response.

What is determinate growth?

growth that stops when adult state is reached (most animal growth, some plant organs like flowers)

A study that assessed the hypothesis that adding the phrase "contains probiotics" to a yogurt container increases sales. Yogurt containers were displayed near each other in a store with and without a "contains probiotics" label. The containers and yogurts were identical in all other ways. Based on the data below, what conclusions, if any, can you draw? no probiotic label bar:::: more monthly sales probiotic label bar:::less monthly sales (statistically significant) A. The results support the hypothesis that adding the phrase "contains probiotics" to a yogurt container increases sales. B. The results do not support the hypothesis that adding the phrase "contains probiotics" to a yogurt container increases sales. C. No conclusions can be drawn from this analysis.

The results do not support the hypothesis that adding the phrase "contains probiotics" to a yogurt container increases sales. Statistical significance indicates that the probiotic labeled container is in fact statistically lower than no probiotic label bar which can allow for the conclusion to be drawn that the results do not support the hypothesis because the monthly sales of "no label" container were higher.

Describe the function of stomata and explain why an ability to regulate opening and closing of stomata is important for plants.

The stromata (leaf pores) allow carbon dioxide in and oxygen and water out//allows gases to move in out of leaf. Open stomata allow the uptake of carbon dioxide for photosynthesis-Closed stomata prevent excess water loss Stomata take in carbon dioxide and release water and oxygen that is a bio product of light and carbon dioxide being absorbed. The ability to open and close stomata helps when underneath drought stress they can retain even further water content