Archive for March, 2011

Looking at cells

Wednesday, March 30th, 2011

cheek cells by Ah Pao on flickr

This week we’ll be getting the microscopes out and you will be making your own slides of different cells.  On the link below you will find the instructions for how to do this.  I suggest you read them before class.  This will save you time in the lesson, and you will be able to make more slides 🙂

Observing cells with light microscopes

plant cells leaf by Ah Pao on flickr

Once you have made your slides, you will be expected to draw biological diagrams of what you observe.  The rubric that will be used to assess these drawings is here:

Grade 9 Rubric for the marking of scientific drawings 

Cell structure and diversity

Wednesday, March 30th, 2011

nerve by estherase on flickr

Take some time to click through this site to learn more about cells and their structures.   Here is another good place to learn about cells.   Look through each site and then leave me a comment as to which of them you preferred and WHY

If you find any other sites on this topic that you think would help your classmates learn, please include them in the comments too.

Here is a link to a quiz that you can use to check your understanding of cells.  It is brief – my advice is that you study the structure of prokaryotic and eukaryotic cells, and their functions, and their differences, then see how you go on the quiz.  The answers are on there too, so you can self-assess.

Quiz – cell parts and their functions

What do all cells have in common?

Why do cells differentiate?  Within the same organism, there are differences between cells – why is this?

Here’s what you need to do:-

  1. In your groups, make a list of all the different types of cells you can think of (eg, red blood cell, leaf cell)
  2. Each student chooses ONE cell type to research.  Draw the basic structure, state its function, describe why it is unique, and where it is found.
  3. Share your findings with your group.
  4. Discuss the similarities and differences between the cells you described.  Are cells more alike or more different from one another?  Are some cells more complex than others?  Which ones? 
  5. Try to explain why cells have these similarities and differences.

Oceans topic performance task

Wednesday, March 30th, 2011

Flooding from tsunami near Sendai, Japan by NASA Goddard Photo and Video on flickr

No one can have failed to be shocked by the recent earthquake and tsunami in northern Japan. 

The final perfomance task for this unit requires you to take what you have learned about water, solubility, osmosis, and use it to answer this problem:-

Read this document for details of the performance task.  oceans performance task

Here are the rubrics that will be used to grade your work. Rubric for performance task – oceans  FINALRubric DCP

Saltwater vs freshwater ecosystems

Wednesday, March 30th, 2011

mangrove reflections by Claire `a Taiwan

Plants and animals that live in saltwater and freshwater must have special adaptations to cope with their particular environments.  They need to ensure that they can access water and oxygen at all times.  This can be difficult in circumstances where a plant’s root are surrounded by sea water, as this can affect osmosis. 

Your task is to select one freshwater animal and one saltwater animal and compare their adaptations in the form of a table.  You should then do the same for one freshwater plant and one saltwater plant.  The focus of this exercise is for you to identify the specializations of each species and how it is adapted for it’s environment.  Think about how it accesses water and oxygen.  Think about how it excretes waste.  Here are a few links to get you started, but you should extend your research beyond this.

How plants cope in the mangroves.  Mangrove trees.  How do plants survive in salt water?   Freshwater plant adaptations

Freshwater vs saltwater fish.    Animal adaptations.   Bullsharks.    Why do saltwater fish die when put in freshwater?

Reproduction in flowering plants

Wednesday, March 30th, 2011

White flower by doug88888 on flickr

Flowers are the reproductive organs of angiospermophytes.  You will get the chance to disect one, and to draw and label it.  Some flowers are pollinated by wind, others by insects.  We’ll focus on the insect pollinated ones in this topic.  You will also need to be able to distinguish between these three processes:- pollination, fertilization and seed dispersal.

We’ll then take a look at seeds and seed structure, and the process of germination.  Finally we will learn about phytochromes and their role in controlling flowering in long-day and short-day plants.  Read about photoperiodism here.

Be prepared to do some independent reading from your textbooks on this topic.  Here is Mr Taylor’s presentation.  And here is another useful one. Reproduction in angiospermophytes

Transport in plants

Thursday, March 17th, 2011

Cactus series by PVCG on flickr

Here is Mr Taylor’s presentation on this topic.  Transport in angiospermophytes

  • How do water and mineral ions enter a plant?
  • How does water move upwards, against gravity, in a plant stem?
  • What is transpiration and what are the factors that affect it?
  • How are plants adapted for particularly dry or wet environments?

We will also set up a lab to investigate which surface of a leaf transpires the most, and learn what a potometer is and how to use it.

Cell structure

Wednesday, March 16th, 2011

cells by Dougal Campbell on flickr

Watch this brainpop video on cells to introduce the topic.  For more detail on cell structures, watch this.   For comparisons on plant and animal cells and cell specialization watch this.

You need to be able to do the following:-

  • Draw and label a diagram of a simplified animal cell.
  • Draw and label a diagram of a simplified plant cell.
  • State the functions for each of the labels on the above diagrams.
  • Compare animal and plant cell structure and relate to their functions.
  • Understand that cells are differentiated for their functions, and give some examples of these specializations.

Water cycle

Friday, March 11th, 2011

rain by DRB62 on flickr

Your task is to research the water cycle, then create a story in comic life to represent it. 

You should include the following processes in your work: evaporation, precipitation, transpiration, condensation, infiltration, capillary action, run off. 

Here are a few links to help get you started: water cycle  more water cycle  brainpop video

Historical biology or biological history?

Friday, March 11th, 2011

microscope by staceyjoy on flickr

This week we’ll be looking at the development of the cell theory.  You will need to research the contribution made by each of the following scientists, find a picture of the person or what they made or saw, then use the information to construct a timeline.  Put all that into a presentation of some kind  [prezi / dipity /anything else appropriate].  Your presentation should also include the main points of the cell theory.  Enter the url of your work as a link in a comment on this post.

1.      Hans and Zacharias Janssen

2.      Robert Hooke

3.      Anton Leeuwenhoek

4.      Matthias Schleiden

5.      Theodor Schwann

6.      Rudolf Virchow

7.      August Weismann

Can you label the parts of the microscope on this drawing? Parts-of-a-microscope

Plant structure and growth

Thursday, March 10th, 2011

twig and tendril by stonebird on flickr

As we embark on topic 9, here is the syllabus outline: Topic 9 – Syllabus outline

This topic can be broken into 3 sections:  structure and growth, transport, reproduction.  This document has notes on all of this. Plant Science Topic notes

We’ll start with plant structure and growth.  Plant structure & growth  Here is Mr Taylor’s presentation on this section.

Some things we’ll discover in this section:

  • why do plants grow towards light?
  • how can you tell if a plant is a monocotyledon or dicotyledon?
  • how can plants modify their roots, stems and leaves for different functions?