Grade 9 Biology Book

[Grethe Presnar]

Agrade is a taxon united by a level of morphological or physiological complexity. The term was coined by British biologist Julian Huxley, to contrast with clade, a strictly phylogenetic unit.[1]

An evolutionary grade is a group of species united by morphological or physiological traits, that has given rise to another group that has major differences from the ancestral group's condition, and is thus not considered part of the ancestral group, while still having enough similarities that we can group them under the same clade.[clarification needed] The ancestral group will not be phylogenetically complete (i.e. is not a clade), and so will represent a paraphyletic taxon.[citation needed]

The most commonly cited example is that of reptiles. In the early 19th century, the French naturalist Latreille was the first to divide tetrapods into the four familiar classes of amphibians, reptiles, birds, and mammals.[3] In this system, reptiles are characterized by traits such as laying membranous or shelled eggs, having skin covered in scales or scutes, and having a 'cold-blooded' metabolism. However, the ancestors of mammals and birds also had these traits and so birds and mammals can be said to "have evolved from reptiles", making the reptiles, when defined by these traits, a grade rather than a clade.[4] In microbiology, taxa that are thus seen as excluded from their evolutionary grade parent group are called taxa in disguise.[5]

Paraphyletic taxa will often, but not always, represent evolutionary grades. In some cases paraphyletic taxa are united simply by not being part of any other groups, and give rise to so-called wastebasket taxa which may even be polyphyletic.

The traditional Linnaean way of defining taxa is through the use of anatomical traits. When the actual phylogenetic relationship is unknown, well defined groups sometimes turn out to be defined by traits that are primitive rather than derived. In Linnaean systematics, evolutionary grades are accepted in higher taxonomic ranks, though generally avoided at family level and below. In phylogenetic nomenclature evolutionary grades (or any other form of paraphyly) are not accepted.[6]

Where information about phylogenetic relationships is available, organisms are preferentially grouped into clades. Where data is lacking, or groups of uncertain relationship are to be compared, the cladistic method is limited and grade provides a useful tool for comparing organisms. This is particularly common in palaeontology, where fossils are often fragmentary and difficult to interpret. Thus, traditional palaeontological works are often using evolutionary grades as formal or informal taxa, including examples such as labyrinthodonts, anapsids, synapsids, dinosaurs, ammonites, eurypterids, lobopodians and many of the more well known taxa of human evolution. Organizing organisms into grades rather than strict clades can also be very useful to understand the evolutionary sequence behind major diversification of both animals[7] and plants.[8]

Evolutionary grades, being united by gross morphological traits, are often eminently recognizable in the field. While taxonomy seeks to eliminate paraphyletic taxa, such grades are sometimes kept as formal or informal groups on the basis of their usefulness for laymen and field researchers.[6] In bacteriology, the renaming of species or groups that turn out to be evolutionary grades is kept to a minimum to avoid misunderstanding, which in the case of pathogens could have fatal consequences. When referring to a group of organisms, the term "grade" is usually enclosed in quotation marks to denote its status as a paraphyletic term.

With the rise of phylogenetic nomenclature, the use of evolutionary grades as formal taxa has come under debate. Under a strict phylogenetic approach, only monophyletic taxa are recognized.[9] This differs from the more traditional approach of evolutionary taxonomy.[10] The difference in approach has led to a vigorous debate between proponents of the two approaches to taxonomy, particularly in well established fields like vertebrate palaeontology and botany.[11] The difference between the statement "B is part of A" (phylogenetic approach) and "B has evolved from A" (evolutionary approach) is, however, one of semantics rather than of phylogeny. Both express the same phylogeny, but the former emphasizes the phylogenetic continuum while the latter emphasizes a distinct shift in anatomy or ecology in B relative to A.

Welcome to the Science webpage for the Utah State Board of Education. On this page, you will find details about state science standards, endorsement information, science teaching resources. Peruse, enjoy, and if you have any questions, please contact us.

The Utah State Board of Education (USBE), in January of 1984, established policy requiring the identification of specific core standards to be met by all K-12 students in order to graduate from Utah's secondary schools. The USBE regularly updates the Utah Core Standards, while parents, teachers, and local school boards continue to control the curriculum choices that reflect local values.

This document was created for students, parents, teachers and school leaders as an information resource to better understand the State Science with Engineering Education (SEEd) Standards: Preparing Students for a Lifetime of Understanding New Science Standards Success

The Utah State Board of Education, in collaboration with the Utah Education Network (UEN), has created two e-mail listservs for science teachers to learn more about Utah science events and professional development. One is focused on elementary (K-6) science and the other on secondary (6-12) science. Use the links below to register for the e-mail listserv.

The Science Core Guides are created to provide guidance for developing effective instruction aligned to the Utah Science with Engineering Education (SEEd) Standards. They are intended to support teachers, administrators, science specialists, instructional coaches, parents, and other stakeholders as they plan instruction at a local level.

The Core Guides are not intended to be read from cover to cover. They are meant as a resource document to be used, when needed, to support teacher professional learning and curriculum decisions. They are not meant to be used by students, and therefore they may not be written in student-friendly language. The Core Guides are meant to inform teachers and leaders as they make science curriculum decisions.

The Utah State Board of Education desires that all educators in Utah are fully qualified to teach the courses they are assigned to assure that all students get the best education possible. All secondary science courses (Grades 7-12) require specific secondary science endorsements for teachers to be eligible to teach them.

USBE uses competency-based endorsements The Secondary Science Endorsements Requirement Area Options (Google Doc) document summaries the options available to demonstrate competency in the requirement areas for each Secondary Science Endorsement in a one page table format.

Many universities offer online courses that can be taken to fulfill endorsement course requirements. These courses vary from semester to semester and vary in price from university to university. Some universities also require a small payment to become a matriculated student and gain a student identification number. Please be sure to read all university requirements to assure that you are eligible, can meet prerequisite requirements, and can successfully take the course.

The Utah Science Teaching Association (UtSTA) has partnered with local universities to offer endorsement courses for university credit. See the Endorsement Course (Utah Science Teaching Association) webpage on UtSTA's website (Utah Science Teaching Association) for the available online and in-person courses that are offered.

As part of the application for a secondary science endorsement, the Utah State Board of Education (USBE) asks that all applicants complete a safety certification. There are three options for Safety Certification:

The purpose of these courses is to build and support teacher science conceptual knowledge of the Disciplinary Core Ideas (DCIs) used within the SEEd Standards. The Grade K-6 courses are developed specifically for elementary educators and therefore only licensed K-6 teachers will be awarded USBE credit upon completion.

For these content courses, each grade level or content area has one main course in which to enroll. Within the course, there are mini-courses that explore the content knowledge expectations of each strand within the SEEd Standards for that grade level. The number of mini-courses available for each grade level are equal to the number of strands within the SEEd standards for that grade level. Educators may select which mini-courses they want to pursue and the order they want to take each one after a short introduction module is completed within the main course. Educators do not need to complete all of the mini-courses. Credit for the K-5 mini-courses is either .5 or 1.0 for each strand mini-course depending on the number of standards within the strand (2-5 standards = .5, 6+ standards = 1.0). Credit for 6-8 courses is listed as you sign up for the course. Credits will post in MIDAS three times during the year as delineated in Table 1 below. These courses are free for participants and are self-paced. Educators may register at any time.

Completing content courses for Grades 6-8 do not qualify teachers to meet requirement areas for a Science Core Endorsement. For information on the course requirements for this teaching endorsement, review the Secondary Science Core Endorsement Specs document.

To receive credit for a mini-course or for the K-12 Introduction to Three-Dimensional Instruction course, educators enrolled in any of the courses must receive 90% on the quizzes, complete the discussion posts, and submit the required feedback survey for the mini-course or the entire Introduction course. Once enrolled in a course the participants will continue to have access to the Canvas course content even after they are finished so that it can be used as a reference in the future. Credit will be assigned three times during the year as delineated below.

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