SC15.BIO.5

Science (2015) Grade(s): 09-12 - Biology

Planning and Carrying out Investigations

Structure and Function; Stability and Change

Students know:

A negative feedback loop is when the body senses (receptor) an internal change (stimulus) and activates mechanisms (effector) that reverse, or negate (response) that change (e.g., Regulation of body temperature).
The positive feedback loop is a process where the body senses a change and activates mechanisms that accelerate or increase that change—can aid in homeostasis but also can be life threatening (e.g., blood clotting (helpful), response to myocardial infarction (potentially fatal).
The chemical structure of the phospholipid membrane and the various ways large and small molecules move between the inside and outside of the cell to maintain homeostasis.
The movement of water is a cellular response to different solute concentrations within and outside the cell.

Students are able to:

Investigate and communicate factors that affect homeostasis in living organisms.
Develop an answerable scientific question and plan and carry out an investigation that provides data about homeostasis.
Investigate the function of the plasma membrane in relation to cellular processes that maintain homeostasis within the cell.
Observe and explore simple experiments to develop a working list of the properties of water.
Use a model to explain the properties of water at a molecular level.
Use a model to illustrate chemical interactions between water molecules and other polar and non-polar compounds.
Design an experiment that provides data regarding one property of water and communicate the experimental design, results and conclusions.

Students understand that:

Homeostasis is the tendency of an organism or cell to regulate its internal environment and maintain equilibrium, usually by a system of feedback controls, so as to stabilize health and functioning.
A complex set of chemical, thermal and neural factors interact in complex ways, both helping and hindering the body while it works to maintain homeostasis.
Water movement is critical to the maintenance of homeostasis for cells and vascular systems.