Vas Bio Tutorials

Lesson 18: Chapter 4 - Chemical Composition in a Cell

Hi students, schools are still closed due to Covid19. The lesson for today is on Chapter 4- Chemical composition in a cell. Maybe some of you would not have been taught this chapter in school due to Covid19.

Lesson 17: Answers to questions in Lesson 16.

Hi students, stay at home during this MCO period. Revise your lessons. Here are the answers for the previous questions.

Lesson 16: Questions on the Plasma Membrane

Lesson 15: Answers to HOTS questions in Lesson 10

Lesson 13: Answers for questions given in Lesson 9

Lesson 12: Isotonic, Hypotonic, Hypertonic Solutions and their effect on plant and animal cells.

Hi students, the school holidays has just begun. Happy holidays and try to be indoors as far as possible to avoid Covid19.

Today's lesson will be short notes on the three types of solutions and the effect on plant and animal cells. I am also posting a picture of my lab class where my students produced beautiful chilly flowers using the concept of osmosis. You can also try at home.

Lesson 11: Movement of Substances across the Plasma Membrane

Hi students, today we start a new chapter. In this chapter, importance is given to the plasma membrane. It is through this plasma membrane that water and nutrients are absorbed into the cells, our waste products are excreted from the cells and the exchange of respiratory gases takes place here.

The detailed structure of the plasma membrane is seen under an electron microscope. During my class, I created models of the plasma membrane using matchsticks, plasticine, groundnuts and strands of meehoon. My students also created beautiful models using beads, coloured pins etc.

So in today's lesson, I will first post some short notes on the structure of the plasma membrane and the methods of transport of substances across the plasma membrane. I will also show you simple models of the phospholipid bilayer and the transport of substances.

Lesson 10: HOTS questions.

Today I am posting HOTS questions on cell structure and function. Do send me your answers in the comments section.

Lesson 9: Notes and Structured Questions:

Hi students, hope you had a good weekend.

Today's lesson is on short notes on phagocytosis in Amoeba sp. and osmoreguation in Paramecium sp., two popular sub questions that appear in SPM sturctured questions. I am also giving you 2 structured questions with HOTS skills in them.

Lesson 8: Regulating the internal environment

Internal environment refers to the conditions that exist within the body of an organism, which is the composition of the interstitial fluid and blood plasma.

Homeostasis is the maintenance of a relatively constant internal environment for the optimum function of the cells.

So students, today you will learn how your body keeps the physical and chemical factors in your internal environment in a steady state.

Lesson 7: Cell Organisation

Hi students, today's lesson is on cell organisation which I have delivered to you in the form of a flow chart.

Answers for MCQ in Lesson 2.

Answers for structured question in Lesson 2.

Hi, I am Vasantha, a retired Biology teacher. This blog is specially for students taking Biology SPM Malaysian syllabus. My tutorials are mainly hand on activities, to generate interest in learning Biology. Notes, mind maps and HOTS questions are also part of these tutorials. I hope this blog will benefit Biology students and to get good feedback from the students.

Lesson 6: Models of Paramecium sp.

I hope you had fun making models of Amoeba sp. As a teacher, I always encourage my students to create themselves learning modules, as they will remember and understand concepts better in this manner, compared to just learning from textbooks. Textbooks are 2D source of information but models are 3D.

Today I am uploading models of Paramecium sp. , created by my students. The first model used styrofoam to form the slipper shape of Paramecium sp., sponge cut into star shapes to represent contractile vacoules, plasticine for micro and macro nucleus, strips from plastic bags were cut and pasted all around the model to represent the cilia. This model was interesting as when it was immersed in a basin of water, it floated and the strips of plastic all opened up beautifully.

The second model was also unique. My students used the back of a slipper to represent the Paramecium sp. They used a narrow leaf to represent the oral groove, star anise for contractile vacuole and groundnuts for micro and macro nucleus. For the cilia, they cut the fringes from a towel and glued it all around the slipper. Simply amazing, these students.

Do try making these models and if you have come with a new model, do take pictures of it and post in the comments section.

Lesson 5: Binary fission in Amoeba sp.

After guiding you on how to make a phagocytosis model for Ameba sp. , today you will learn to make a model for the asexual reproduction known as binary fission.

Materials needed:
Plasticine
Pepper corns
A4 paper

Method:
1. Make an Amoeba sp. with the nucleus in it
2. Pull the plasticine model inwards to show
the pseudopodia are pulled in.
3 At the same time, place two pepper corns
to show that the nucleus has divided.
4. Now pull the model further to form a bridge
and this shows that the cytoplasm has
divided.
5. Lastly form 2 models of Amoeba sp. to
show that two daughter Amoeba sp. are
formed.

Lesson 4: Living processes in unicellular organisms
Amoeba sp.

Hi students, after the tutorials on cell stucture, and questions, today's lesson is on Amoeba sp. , a unicellular organism that carries out its main living processes within itself.
The activity for today is to make models of Amoeba sp. carrying out its feeding process or also known as phagocytosis.

Materials needed:
Plasticine of two colours
Pepper corns
Mustard seeds
Mysore dhall red
Yellow moong dhall
A4 paper

Method:
1. Make Amoeba sp. about 5.
2. Put the pepper corn to represent nucleus.
3. Put the red mysore dhall (food)near it and
form the pseudopodia so as to engulf it.
4. Form a small flat circle with another
plasticine colour and put the red mysore
dhall on top to form the food vacuole.
5. Place the yellow moong dhall near to food
vacuole to show it fusing with food vacuole
This represents the lysosome.
6. Pound the red mysore dhall into small
pieces and scatter them on the Amoeba sp.
to show the the food particle has been
digested by the the lysozyme in the
lysosome.
7. Put some mustard seeds at the rear end
of Amoeba sp. to show the expulsion
of undigested material.

Note: This phagocytosis process appears in
essay or structured questions in SPM.

Lesson 3: MCQ on Cell Structure

Try answering these questions and send me the answers in the comment section.

Lesson 2: Cell Structure

Hi students, have you tried making the models of plant and animal cells using bread? If you have, do take pictures and send them to me in the comment section.

Today's lesson will be on short notes on the functions of the organelles. Try transferring these notes into mind map, one for animal cell and one for plant cell and send it to me.

I am also posting a structured question based on what I have explained in Lesson 1 with some higher thinking level questions or HOTS questions.

Learning Biology is Fun

Lesson 1 : Form 4 - Chapter of Cells Structure & Cell Organisation.

Activity: Creating Models of Plant & Animal Cells

1. Get all your materials need to build the
models
• slices of bread
• yellow noodles
• flat white rice noodles
• groundnuts
• snow peas
• potatoes
• carrots
• star anise
• pepper corn
• mustard seeds

2. Keep one slice of bread as it is , this is plant
cell. Cut the other slice into a circular
shape, this is the animal cell, trim off the
edges ( no cell wall). Put both slices on
white paper for writing the labels.
3. Split the groundnut open, remove the seeds
using a marker pen, outline the edges, this
Is the mitochondria.
4. Arrange the flat white rice noodles to
resemble the Golgi apparatus.
5. Cut very fine strands of carrot, this is the
chromosomes.
6. Cut the potato to a round slice, then cut off
the inner part to get a ring shape. Cut this
ring at intervals, this is the nucleus with
nuclear pores.
7. The pepper corn is the nucleus.
8. The mustard seed are ribosomes.
9. Cut the snow peas to an oval shape, this
is chloroplasts for plant cell.
10. The star anise is the centriole for animal
cell.
11. The yellow noodles are endoplasmic
reticulum.
12. Now assemble the plant and animal cells.
13 Place the potato ring on the centre of each
slice, place the yellow noodles from the
cut part of the potato ring, arranging the
noodle in a zig zag pattern.
14. Place the mustard seeds on top the noodle
this is the Rough Endoplasmic Reticulum.
15. Leave some noodles without mustard
seeds, this is Smooth Endoplasmic
Reticulum.
16. Place the snow peas chloroplasts on the
plant cell and the star anise as cebtriole
on the animal cell.
17. Arrange the white flat noodles like stacks
on both cells as Golgi apparatus.
18. Place the fine carrot strands inside the
potato rings oh both cell, theses are
chromosomes and put the pepper corn
as the nucleolus.
19. Place the groundnuts on both slices,
these are mitochondria.
20. Now label all the organelles that you have
placed on the cells neatly.

Note: The materials as shown in the image
were used by my students. The
procedure I explained, is another
alternative.

Hi, I am Vasantha, a retired Biology teacher in Kuala Lumpur. I am starting this blog with the aim of guiding Biology students to prepare them for SPM (Sijil Pelaran Malaysia). My tutorials are mostly hands on activities which the students can carry out themselves to understand biological concepts. I hope to get the support from students. Thank You.