FUNDAMENTAL UNIT OF LIFE

So here I'm Class IX, with your remaining cell Organelles:

Lysosomes
Ribosomes
Vacuoles
& Centrosomes

Here's the link for the lecture.

Leave comments, ask doubts and keep learning
Good Luck

Life Processes: Human Nutrition (Part II)

Hi Guys

We were left with few parts of human digestive system, specifically:

1. Stomach
2. Small Intestine
3. Large Intestine

And then the processes of absorption via Villi

and a little bit about of Liver & Pancreas

So here we're covering these.

With this we finish the Human Digestive system and all aspects of Nutrition.

Next We'll be starting with respiration.

But for now as usual, we've few questions to solve and few assignments to complete. so watch carefully.

Good Luck

FUNDAMENTAL UNIT OF LIFE (Part 4)

Hey you all,
Welcome back to the next topic.
This one's for class 9.
Here we'll be discussing the most important part of cell

THE NUCLEUS

In this lesson, we've already covered the following:

•Cell: Discoveries

•Cell Theory

•Cell Membrane

•Transport across Cell Membrane

•Cell Wall

And now we cover:

•Nucleus – Organisation & Functions

•Prokaryotic Vs Eukaryotic

•Prokaryotic Organisms

So we start with this video lecture

The most important diagram to practice:

Now the questions:

1. Name two cells/organisms which have more than 1 nucleus.
2. Name the 4 parts of cells and give one unique feature of each.
3. Draw a Prokaryotic cell and label all its parts.
4. Differentiate between Prokaryotic & Eukaryotic cells. Give one example of each.
5. Name one cell organelle that is present in prokaryotic cell, but not found in eukaryotic cell.

So keep learning & keep enjoying.

Don't forget to leave comments & share if you find this useful.

REPRODUCTION IN ORGANISMS (Part 5)

This one for class 12, back again with lesson 1:

Here we cover the following topics:

Gamete transfer:

• When both gametes are motile
• when one is motile, other is not
• When both are non-motile

& Fertilization:

Internal vs External

and a special case

PARTHENOGENESIS

To understand the above here's the video lecture

Here are the questions based on the lecture above:

1. Name some agents of gamete transfer.
2. Define syngamy? What happens if it fails?
3. Differentiate between internal and external fertilization.
4. What additional preparation is required by an organism performing external fertilization & why?
5. How is reproduction in rotifers unique? Name some other organisms showing similar reproductive strategy.

Ask doubts & share comments. Keep learning. 

FUNDAMENTAL UNIT OF LIFE (III)

Welcome to the third video for Lesson 5 of NCERT class 9 Science Books.

We've already covered:

•Cell: Discoveries

•Cell Theory

•Cell Membrane

•Transport across Cell Membrane

In this session we'll try to discuss:

•Cell Wall In Fungi, Plants & Bacteria

•Structure of Cell Wall

• Role of Cell Wall

•A 🎁 surprise topic

So get set go. Here's the link of the video:

At the end of the video, I've given a few questions as assignments for you to check your recall. I give them here again:

1. Find the name of animal group where chitin is found.
2. Give three differences between Cell membrane & Cell wall.
3. Why does the skin of your hands shrink when you wash clothes?
4. If the Rheo leaves in above activity are boiled first and then kept in Salt solution, what kind of results will you get?
5. Make a flash card showing structure & function of Cell wall in Plant Cells.

Keep Learning & stay Safe.

Don't forget to post comments, queries & feedback.

Life Processes - 5

Class 10
Welcome Back 
We're here to study Life Processes
& This time we start with Human Nutrition

Today we'll cover:

1. Digestive System - Diagram
2. Digestion in Mouth
3. Passage of food through food pipe 
4. Peristalsis

So here's the Video

Watch the video, understand the concepts & then try to answer the following questions:

1.Which two types of digestion occur in mouth? Does any type of digestion occurs in Oesophagus?

2.What are the three components of saliva? What are their roles?

3.Define Peristalsis?

4.Draw a labelled diagram of Human Digestive System.

5.Name one type of movement performed by your body while you take a nap after lunch.

Enjoy 👍👍

Life Processes 4

Welcome Back 

This one's for class 10 students.

This is the 4th one for Life Processes. In this we'll start with Heterotrophic Nutrition. 

The Topics we've already covered are:

1. Movements in living organisms
2. Autotrophic Nutrtion

The topics covered in this one are:

1. Types of Heterotrophic Nutrition
2. Holozoic Nutrtion
3. Nutrition In Amoeba & Paramecium

Now without further ado, here's the video for above topics

Try to follow the video, watch it till the time concepts are clear to you.

I've also given you some questions to check your understanding of the concepts covered. Please remember that these answers to these questions are not to be crammed and written. 

Try writing them after watching the video, in your own words. Your answers should reflect the understanding of your concepts.

Sharing the questions here too

´What is heterotrophic nutrition?

´What is the role of decomposers in our environment?

´Write the difference between nutrition of Herbivore, Carnivore & Omnivore. Give 3 examples of each.

´Give some examples of parasitic organisms. Try giving at least one example from both plants and animals.

´What is the role of decomposers in our environment??

Good Luck. Happy Learning & Stay safe 👍

REPRODUCTION IN ORGANISMS PART 3

Sexual Reproduction:

Learning Outcomes: 

After watching this video you will be able to:

1. Define and deduce the key features of sexual reproduction 
2. Identify the patterns of sexual reproduction 
3. Classify organisms on the basis of patterns
4. Understand key terminologies related to sexual reproduction 

Also, I’ve uploaded the video lectures on you tube. So hereafter I’ll be sharing links:

I'll also recommend a watch of this wonderful video on Marsupials.

Watch the video, and thereafter I’ll be sharing a few questions based on topics covered.

Happy Learning 

LIFE PROCESSES (PART III): NUTRITION IN PLANTS

This video post is for Class X students. continuing the previous lecture on Nutrition in Plants. In this video we'll cover the following:

1.  Experiment to determine carbon dioxide is essential for photosynthesis
2. Stomata: Opening & Closing Mechanism

With this we conclude the material on Nutrition in Plants, in the Life Processes lesson.

You'll be solving the questions given.

LIFE PROCESSES II (NUTRITION)

In the next in the series of video for class X, Lesson 6, here is a short video explaining:

1. What is Nutrition
2. Types of Nutrition
3. Autotrophic Nutrition
4.  Activity to show chlorophyll is essential for photosynthesis

Leave queries & comments.

Good Luck

FUNDAMENTAL UNIT OF LIFE (PART II)

CLASS IX

Continuing with previous lecture on Cell: Fundamental Unit of Life for Class IX

This one covers #CellMembrane to develop a basis for study of transport across cell membrane.

Please follow carefully.

This video is followed by 4 more to develop an understanding of the types of transport across cell membrane.

Next we'll be doing some questions on the topics covered till now.

Understand, enquire & apply.

REPRODUCTION IN ORGANISMS PART II

In continuation with our previous discussion about introduction of first chapter, I'm uploading the second part.
In this part we'll be discussing Asexual reproduction: Modes & Significance.
Go through the video and try solving the assignments in between as well as at the end.

Class IX: Fundamental Unit Of Life (Part 1)

Welcome to Class 9.

Here is a lecture VDO for Chapter 5 of NCERT Class 9 Science Books.

Listen carefully and make notes based on the slides.

Happy Learning

Ask questions, clear doubts. Stay in touch

Reproduction In Organisms VDO Lecture

Covid 19 has put on hold many things. The one thing it need not derail is learning.

So here I'm uploading lecture for the first topic of #ClassXII Biology Lesson 1, Reproduction In Organisms.

Stay Connected & Keep Learning

RNA Interference

RNA interference in Unit IV of class 12 Biology is a concept that students find as difficult to grasp as teachers find it difficult to simplify. 
Though the basic concept is quite simple yet it becomes complex since some of the steps are beyond the grade level, and hence conveniently skipped in NCERT text books. with key steps missing you simply cannot grasp the concept.
So here is an easy to understand ppt, explaining the basic concept as well as required background knowledge.
Students can revisit these concepts.
Ask questions where you get stuck. consult your teachers. you may post queries here as well.
So here is the link for the ppt:
RNAi

and a few images

Meloidegyne incognita

Infected Root

Short Test ECOSYSTEM

Ecosystem

Try solving in 20 minutes

1. State the difference between the first trophic levels of detritus food chain and grazing food chain.
2. 8How does primary succession start in water and lead to the climax community? Explain.
3. Why are the pyramids referred to as 'upright' or 'inverted'? Give two examples of inverted pyramids.
4. Why are energy pyramid always erect?
5. Write the equation that helps in deriving the net primary productivity of an ecosystem. Differentiate between primary & secondary productivity.
6. Explain the simplified model of carbon cycle in nature.

Practice Paper: class XII

Lesson Covered:

Strategies for Improvement in Food Production
Microbes in Human Welfare
Biotechnology: Principles & Applications

Time: 1 ½ hour                                                                                                                       MM 40

Instructions:

Q 1-5 (1 mark), 6-10 (2 marks), 11-15 (3 marks), 16-17(5 marks)

1.       Name the first transgenic cow developed and state the improvement in the quality of the product produced by it.

2.       Name the vector used for transferring nematode specific gene in tobacco plant.

3.       What is SCP? Name the organism used for production of SCP.

4.       A resistant variety of Abelmoschus esculentus show resistance against a virus. Name the virus and plant variety.

5.       “A person is suffering with high blood cholesterol.” Which kind of bioactive molecule you will suggest to reduce his cholesterol level?

6.       A banana herb is virus infected. Name the method that will help in obtaining healthy banana plants from this diseases plant.

7.       Name the insect pest killed by the product of cryIAb gene. Explain how this gene makes the plant resistant to the insect pest.

8.       What is activated sludge? Where is it produced? Why is it named so?

9.       What is inbreeding depression. How can it be overcome?

10.   How are sugarcane varieties with high yield, thick stem, high sugar formed that can be grown in North India?

11.   Explain the term MOET. Which hormone is used for this method. Give the key steps of MOET.

12.   What are palindromes? Where are they used?

13.   What was Cohen & Boyer’s contribution to field of Biotechnology? Show diagrammatically.

14.   What is PCR? Where is it used. Represent the key steps diagrammatically.

15.   Draw a well labelled diagram of a cloning vector showing:

Ori, rop, atleast two restriction sites & 2 antibiotic markers. Give function of each.

16.   (a)Write any one drawback of selection of recombinant due to inactivation of antibiotic. Explain how recombinants and non-recombinants are differentiated on the basis of colour production in the presence of a chromogenic substrate?

     (b)Explain why DNA is not able to pass through cell membrane? Which methods are available to make the plant cell competent to take up DNA from surrounding medium?

17.   Given below is the   sketch of one method used to separate DNA fragments:

                

(a) Give the term caption for above diagram.

(b) At which end would be loaded the samples and why?

(c) Analyse the reason for different positions taken up by the DNA bands.

(d)Elaborate the step he would have followed to visualize DNA bands.

(e) Name the gel used in this technique.

VALUE POINTS: CLASS IX MIDTERM

Sequel to previous post.

marking scheme/value points for the sample paper uploaded earlier:

Q.1   A. Lysosome, B. Golgi Complex, C. Plastid / Mitochondria (any 2) ½×1

Q.2  Exosmosis                                                                                            1

Q.3  Conduction & Xylem                                                                           ½×1

Q.4  Striated/Skeletal Muscle                                                                    1

Q.5  In AIDS patients immune system is not working or weakened.    1

Q.6  Mycelium, Large number of spores                                                   ½×1

Q.7  A. Symptoms, b. acute & chronic, c. bacteria, infectious & defieicency ½×6

Q.8  Fungi, to kill bacteria

Q.9  A. Fungi (heterotrophic, cell wall chitin), Plantae (autotrophic, cell wall cytoplasm)              1×3

B. Monocot (single cotyledon, fibrous root, parallel venation), dicot ( 2 cotyledons, tap root, reticulate venation) – any 2           

C. Porifera (cell level of organisation, non motile), Coelentrata (tissue level of organisation, motile)

D. Piesces (aquatic, streamlined body, fins, gills), amphibians (both terrestrial & aquatic, not streamlined body, legs, lungs as well as gills) – any 2

OR

Whittaker’s 5 kingdom classification                                                                                                       3

Q.10                      3 differences between Prokaryotic & eukaryotic cells & diagram of both.                       5

OR

Parenchyma, Collenchyma & Sclerenchyma (2 differences & diagram)

Q.11                      Glycerine – to prevent from drying; Safranin – to stain                                                    1+1

Q.12                      Cockroach (jointed legs, segmented body, chitinous exoskeleton) – (any 2)    1+2

CLASS 9 MIDTERM QUESTION PAPER

Q.1  Name the cell organelle that:                         1/2×2                                                                                                       

a.       Protects cells from infections & toxins.

b.       Synthesizes complex sugars from glucose.  OR

c.       Contains DNA (other than nucleus)

Q.2   While cooking vegetables adding of salt causes the vegetables to release water, thus allowing vegetables to be cooked. Which process is responsible for release of water due to addition of salt?                      1

Q.3   A white flower was kept in red coloured water overnight. By morning the flower turned red. Which process & which tissue is responsible for the red colour of flower?                                                      1

Q.4   An athlete increases his speed as he closes on to the finishing line. Which muscles help him increase his running speed?                                                                                                                                         1

Q.5  Mucor infection in lungs leads to nasal congestion, wheezing throat irritation or coughing in healthy individuals. However, in AIDS patients it can be fatal. Why?                                                                          1

Q.6   2 characteristic behavioural features of fungi are: they are heterotrophic & they are non motile. What special structural characteristics have they developed to                                                                          1/2×2

a.       Obtain food

b.       Ensure survival

Q.7    Fill in the blanks:                                                                                                                                1/2×6

a.       Signs of disease such as fever, vomiting are known as its __________________

b.       Diseases that last for a short period are known as _____________, and those that persist for long periods are known as ________________

c.       Tuberculosis effects our lungs and is caused due to a ___________ while common cold causes cough is caused due to virus.

d.       Diseases caused due to microbes are known as ______________ disease, while diseases caused due to lack of essential nutrients in body are known as __________________ disease.

Q.8  Which organisms are the source of antibiotics? What is their use?                                                    1+1

Q.9  Differentiate (2 differences) between any 3 of the following groups of organisms:                               1×3

a.       Fungi & Plantae

b.       Monocotyledon & Dicotyledon

c.       Porifera & Coelentrata

d.       Pisces & Amphibia

OR

 What is the most popular method of classification of living organisms? Show with the help of flow chart? Name the scientist responsible for this classification.                                                                                  3

Q.10          You are asked to study cells from curd & plant leaf. What differences would you observe in the cells from these two sources (3 differences). Explain with the help of diagrams.                                       5

OR

Tabulate 2 differences between the three types of permanent tissues. Draw diagrams to show each type.

Section B

Q.11          Onion peel cells are kept in glycerine and treated with safranin before viewing under a microscope. Why are glycerine & safranin used?                                                                                                1

Q.12          Identify the organism & give its 2 distinctive features.                                 1+2