Category Archives: Grade 9 Science

Poaching in East Africa

One of my favorite things about living in Tanzania is the amazing diversity of ecosystems in this country – the grassy plains of the Serengeti, mist-shrouded slopes of volcanic mountains like Kili and Meru, vibrant coral reefs of Mafia and Mnemba islands, the waterfalls and forests of the southern highlands, and the semi-wooded savanna of the Selous all come to mind.

Mikumi savanna.  Image credit: Brad Kremer

Mikumi savanna.
Image credit: Mr Kremer

Habitat diversity like this gives rise to an incredible level of biodiversity, with a large number of endemic species found across Tanzania: Zanzibar red colobus monkeys, Pemba flying fox, the kipunji monkey of the Udzungwa Mountains, Ancistrorhynchus refractus orchids from the Kitulo plateau, plus several native chameleons such as the Usambara two-horned chameleon (pictured below) and the Uluguru one-horned chameleon. Follow this link for a more complete look at Tanzania’s Living National Treasures.

West Usambara two-horned chameleon.  image credit: http://mitschis-chamaeleons.de/

West Usambara two-horned chameleon.
image credit: http://mitschis-chamaeleons.de/

Sadly, Tanzania’s diversity is threatened by a rapidly-growing and highly-lucrative practice – poaching. Most poachers don’t kill or capture animals because they’re inherently evil people; instead, most of them do it because it’s the easiest way for them to earn enough money to feed their families. Food on the table trumps a pretty landscape pretty much every time.

But how does poaching impact Tanzania? What are the effects on the food webs in our beautiful national parks? What are the economic and social pressures on communities near these reserves to either actively participate in poaching or turn a blind eye to it? How does poaching’s links to organized crime influence local and national politics? These are the questions you should address in your next assignment – People and Poaching in East Africa: a One World Analysis.

Below, once again, is the UN document outlining the links between poaching, organized crime, and the illicit drug trade in East Africa. It’s a little dense but still pretty fascinating to read, if you ask me.

Here’s another presentation on elephant poaching, which links east Africa with the Philippines and other parts of Asia.

And lastly, check out this AFP article about a hunting group in Texas, USA, which wants to sell a permit to kill one endangered black rhino in Namibia as part of an effort to save the species. What do you think of this approach?

Photosynthesis and Respiration

Welcome back from the October break! I know you’re all excited to be back in class after a week of sleeping in and lazing around with your friends and families. Hopefully, the following lab experiment will ease everyone back into the routine of school…

The processes of photosynthesis and respiration are essentially inverse reactions. Photosynthesis uses carbon dioxide and water as reactants to produce glucose and oxygen gas. Respiration uses glucose and oxygen gas as reactants to produce carbon dioxide and water. The only difference is that photosynthesis requires an input of light energy to drive the reaction, energy which is stored in the C-H bonds of the glucose molecules produced.

Here you will find the instructions for Lab 31C Photosynthesis-Respiration (CO2 and O2), which I originally planned for the day we return from the break. Unfortunately, most of the science department order has not yet arrived, including our new oxygen sensors, which means we don’t have enough equipment for everyone to get to do the lab. But thanks to modern technology, we can still run the lab virtually! Open the document and read the questions and extensions after the procedure and data tables. These should help guide your thinking with the photosynthesis/respiration labs you’re designing on your own.

Photosynthesis-respiration lab setup. Screen capture image from Vernier Loggerpro.

Photosynthesis-respiration lab setup. Screen capture image from Vernier LoggerPro software.

Grade 9 Biology Online Quiz Feedback

Help me create more engaging and meaningful learning experiences for you by responding to the questions embedded in the form below. Responses are anonymous.

Video

The Carbon and Nitrogen Cycles

Biogeochemical cycles trace the movement of matter and nutrients through living organisms (“bio-“), planetary systems (“geo-“) and chemical reactions (“chemical”) throughout every part of Earth. The carbon cycle and the nitrogen cycle are possibly the 2 most important biogeochemical cycles on Earth. Here are a few fun videos to help you learn about these two essential cycles in our study of life and ecology.

First, a nice explanation of the carbon cycle:

Second, a little carbon music video:

Third, click on this link to BBC Bitesize Science for a very well-thought-out activity about the carbon cycle. It incorporates photosynthesis, respiration, biological molecules, and trophic levels.

Fourth, this animated tutorial found at W.H. Freeman thoroughly explains each step in the nitrogen cycle. While not super exciting, it’s well-done and includes a brief 3-question quiz.

Fifth, CrashCourse Science at YouTube offers us this entertaining and educational video about the nitrogen and phosphorus cycles (You don’t have to know about the phosphorus cycle in this class, but it’s helpful if you take more advanced biology courses):

Energy and Nutrient Flows in Ecosystems

I found this presentation while looking through some stuff over at Slideshare.net, which is a pretty good resource for school notes if you haven’t found it yet. The teacher for this class includes almost everything that we need to know about the differences between the movement of energy and nutrients through and within ecosystems, respectively.

The key points I want you to remember about this topic are as follows:

  1. Energy enters, flows through, and leaves a system.
  2. Nutrients cycle repeatedly within the system.
  3. Most of the energy at any trophic level is lost before it can be used by the next trophic level.
  4. Energy is lost 3 main ways:
    • heat
    • waste (feces and tissue loss)
    • used for respiration

The video below is also fairly helpful. What I like about it is the blank energy and nutrient diagram he fills in as he moves through the ecosystem. It’s a nice approach to a possible future test question (hint, hint).

What’s on the Biology Quiz?!?

Image Credit: by Mark A. Hicks, illustrator, via school.discoveryeducation.com

Image Credit: by Mark A. Hicks, illustrator, via school.discoveryeducation.com

I’ve heard this question a bunch of times already this week, and it’s only Tuesday morning! If you’ve been paying attention in class, you should already have a pretty good idea of what will be on the quiz. If you haven’t been paying attention, I’m going to give you a couple of hints in this post.

Quiz Dates

  • 9A + 9C: Friday 4 October
  • 9B: Monday 7 October

Quiz Format

  • Criterion C1: Explaining Scientific Information
  • Level 1-2 Questions: Matching definitions with vocabulary, labeling diagrams
  • Level 3-4 Questions: Identifying and correcting True/False statements
  • Level 5-6 Questions: Describing and explaining scientific concepts.

Quiz Topics

  • Cell structure and function
  • Biological molecules
  • Ecological pyramids
  • Food webs
  • Trophic levels

The Heirarchy of Life

For homework, please watch the following video from Mr Anderson’s Bozeman Biology channel on Youtube and complete the Google form I sent you. I’ve also embedded the form below the video, but you can only see it when you are logged into your IST gmail account.

Planning the Photosynthesis and Respiration Lab

I’ll add more later, but for the moment, please use this lab report planner to develop the investigation you will design into photosynthesis and respiration in Philodendron hastatum and Sansevieria trifasciata.

Below is a link to the planner as a Google form. When you complete the planner and click ‘submit,’ I will receive a digital version of your responses, which means I can then quickly see what you’re planning for your investigation and give you some timely feedback in class. ***Please note that you must be signed in to your IST Gmail account in order to see and use the planner form!

Click on the following link to download a MS Word version of the planner. It covers all parts of the lab report process in MYP science and is a little more detailed than the embedded Google form above. Photosynthesis-Respiration Lab Report Planner

Photosynthesis Experiment #7

Sansevieria trifasciata

Sansevieria trifasciata

This week in grade 9 science, we’ll start the process of developing your investigations into photosynthesis and respiration in Sansevieria trifasciata and Philodendron hastatum plants. The first steps of that process are a couple of preliminary experiment to establish an understanding of these essential processes.

Philodendron hastatum

Philodendron hastatum

The experiment below is the one we’ll be doing in class on Thursday and Friday of this week. Please make sure you’ve read all the way through the procedure before we start in the lab!

You will submit digital versions of the data tables and the analysis questions for homework after you’ve finished this experiment. You may send them via email.

Video

Biological Molecules

Well, today was a little wacky, with no electricity or projector, class photographs in the middle of one class, and virtually no air circulating in my room to make for a hot hot hot day at school. Add in the noise and distraction of holding class in the courtyard, and we have….well, we have a bit of a mess.

Just so we’re all on the same page of the biology unit, I thought I’d summarize the key points from today’s lesson on biological molecules. Below are the finer points of the lesson.

The 3 major functions of all biological molecules

  1. Instructions
  2. Energy storage
  3. Source of energy

Screen Shot 2013-09-24 at 3.02.57 PMCarbohydrates

  • chains of C, H, and O
  • supply all energy in cells and food chains
  • energy tends to be short-term energy (glycogen)
  • simple sugars such as glucose may build more complex molecules
  • some long chains of sugars, such as cellulose, are used for cellular structure

Screen Shot 2013-09-24 at 3.03.49 PMLipids

  • do not dissolve in water
  • long chains of C, H, O, and P
  • have more bonds than carbs, so they’re used for energy storage
  • slow release of energy
  • saturated fats: all single C-H bonds, tend to be solids
  • unsaturated fats: some C-C double bonds, tend to be liquids (oils)
  • Image credit: http://www.uic.edu

    Image credit: http://www.uic.edu

    phospholipids make up cell membranes and have two main parts:

    • a phosphate group at one end, which is polar (charged), meaning it is hydrophilic
    • the hydrophobic hydrocarbon tails

Proteins

  • most important biological molecule
  • many functions in organisms:
    • enzymes
    • structural components (building blocks)
    • hormones
    • antibodies
  • made of chains of amino acids
  • only 20 amino acids make all the 1000’s of proteins in the world

Nucleotides

  • made of C, H, O, P, and N
  • 3 parts of each nucleotide:
    • nitrogen base
    • sugar
    • phosphate
  • Screen Shot 2013-09-24 at 3.03.33 PM

    4 different nitrogen bases to know: A-C-G-T (shown at right)

  • several functions in organisms:
    • chemical messengers
    • coenzymes
    • carry energy from one part of a cell to another
    • build nucleic acids
  • two kinds of nucleic acids:Screen Shot 2013-09-24 at 3.03.20 PM
    • DNA: sequence of nucleotides makes up the genetic code of an organism
    • RNA: translates the code into specific proteins

And finally, the slides from class…