<< Chapter < Page Chapter >> Page >

Natural sciences

Grade 4

Life and way of living

Module 5

The senses of smell and taste

Activity: To learn more about the senses of smell and taste [LO 2.1]

When you eat, the tongue tastes the taste of the food and your nose smells the flavour. This is how it works:

The openings of your mouth and nose come together in your throat, behind your mouth. The flavours of the food that you eat go to your nose from the back of your mouth. From there, nerves take a message to the brain and the brain tells you what you smell.

The tongue is rough and covered in taste buds to determine different tastes. Write down what the four tastes are that your tongue can identify:

Now pinch your nostrils together with your fingers to close your nose and drink some tea or cooldrink. Why is the taste different?

What have you noticed when you eat while you have a cold?

The sense of smell is very important in the animal world.

Write a proper sentence to say something about the sense of smell of each of the following animals.







Think of other ways in which animals are able to protect themselves because of their sense of smell.

Try this: Ask someone to mark a route with vanilla or vinegar, without you seeing it. Then try to follow the route by depending on your sense of smell!


LEARNING OUTCOME 2: CONSTRUCTING SCIENCE KNOWLEDGEThe learner will know and be able to interpret and apply scientific, technological and environmental knowledge.

ASSESSMENT STANDARD 2.1: The learner is able to recall significant information.


a. sweet

b. salty

c. bitter

d. sour

When the nostrils are pinched together, scents cannot enter the nose, so you will only distinguish sweet, sour, salty and bitter.

In the case of a cold: the same as above.

The sense of smell in the animal world.

Skunk: Protects itself by spraying a strong smelling / pungent secretion in the direction of the enemy.

Jackal: Depends on its sense of smell when hunting. It also has scent glands that secrete scent as it goes along and helps it to find the way on its return.

Dog: Smells very well. Because of their well-developed sense of smell, dogs are used to sniff out drugs, explosives and even people in crowds. They also use their sense of smell when they are hunting.

Antelope: Uses its sense of smell to stay out of danger. If they smell an enemy, antelopes run off very quickly.

Rhinoceros: They also have scent glands underneath their feet to leave messages for other rhinoceroses.

Hoopoe: Birds usually keep their nests very clean, but not the hoopoe. Part of its defence mechanism is to not clean the nest so that the smell will keep predators away.

Questions & Answers

what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
yes that's correct
I think
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
how nano science is used for hydrophobicity
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
what is differents between GO and RGO?
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
Got questions? Join the online conversation and get instant answers!
Jobilize.com Reply

Get the best Algebra and trigonometry course in your pocket!

Source:  OpenStax, Natural sciences grade 4. OpenStax CNX. Sep 18, 2009 Download for free at http://cnx.org/content/col11096/1.1
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'Natural sciences grade 4' conversation and receive update notifications?