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  1. What was the difference in longitudinal growth between seedlings B and F?
  1. What was the difference between the longest and the shortest seedling?
  1. Describe the way in which a seedling's longitudinal growth occurs.

Assessment: Graph

Were you able to answer the questions?

[LO 2.3]


LO 2: Constructing Science Knowledge:

The learner will know and be able to interpret and apply scientific, technological and environmental knowledge.

This is evident when the learner:

  • recalls meaningful information;
  • categorises information;
  • interprets information;

2.4 applies knowledge.


Plant organs: Stems


Assignment 1

  • As you have indicated, the functions of the plant stem include bearing the leaves, flowers and eventually also the fruit, in such a way that they are exposed to sunlight, pollinating agents and fruit distributors respectively.
  • In the case of large trees, the stem, in time, becomes the trunk, which is greatly thickened and strengthened with bark and other structures.
  • Plant stems need to have channels for conducting the main products that have to be moved up and down. If you understand that water has to be conducted from the lowest tip of the roots to the highest tip of the uppemost leaf, you will realise that we need a conducting channel for such water and for mineral salts.
  • The leaves produce starch and sugar, which have to be conducted to all the cells, even to those that are at the furthest tips of the roots, but cannot be conducted along the same channels as the water, because this would lead to confusion. The special channel for these nutrients is known as the PHLOEM.
  • Further variations occur on the outer surfaces of stems.
  • Herbaceous stems are green and fleshy, but woody stems are brown and hard.
  • The annual monocotyledon usually has fleshy, green herbaceous stems and the perennial dicotyledon, e.g. a fruit tree, has hard, woody stems.
  • As we are mentioning fruit trees – they are deciduous, which means that they lose their leaves in autumn.
  • If you know that leaves are the most important part of the plant (and therefore of fruit trees) when it comes to respiration, and that deciduous trees are without leaves during winter, you might ask what they do about respiration. We should actually ask how gas exchange takes place.
  • Examine the brown, woody twigs that you have collected. There is a good chance that you will notice fine white specks on these brown twigs. These are LENTICELS. Lenticels are pores (openings) that facilitate gas exchange during the wintry season.

Assignment 2


Terminal bud : end bud of a stem, where the growing tip is situated.

Apical meristem : growth tip tissue at the end tip.

Internodes: regions of the stem between nodes.

Nodes : region on stem where buds, leaves and lateral shoots will develop.

Leaf nodes : marks on stems where previous leaves have fallen off.

Axil: region in a node where bud growth will take place.

Scale leaves : Protective leaves for the terminal bud and other growth tips.

1. different types of twig – a green, herbaceous type and a brown, woody type.

Main functions of stems:

to carry leaves in such a way that photosynthesis can take place;

to carry flowers in such a way that they can be pollinated;

to carry fruit in such a way that they can be dispersed;

to conduct water and nutrients between leaves and the roots.

Assignment 3:

  • The following column graph shows the longitudinal growth of six different sunflower seedlings (A, B, C, D, E, F) during the first week after germination.

1. histogram have spaces inbetween

2. M – highest growth

3. approximately 6 mm

4. L and N

5. 8-7=1mm

6. 12-6= 6mm

7. cells divide – cells lengthen and differentiate = growth

Questions & Answers

can someone help me with some logarithmic and exponential equations.
Jeffrey Reply
sure. what is your question?
okay, so you have 6 raised to the power of 2. what is that part of your answer
I don't understand what the A with approx sign and the boxed x mean
it think it's written 20/(X-6)^2 so it's 20 divided by X-6 squared
I'm not sure why it wrote it the other way
I got X =-6
ok. so take the square root of both sides, now you have plus or minus the square root of 20= x-6
oops. ignore that.
so you not have an equal sign anywhere in the original equation?
Commplementary angles
Idrissa Reply
im all ears I need to learn
right! what he said ⤴⤴⤴
what is a good calculator for all algebra; would a Casio fx 260 work with all algebra equations? please name the cheapest, thanks.
Kevin Reply
a perfect square v²+2v+_
Dearan Reply
kkk nice
Abdirahman Reply
algebra 2 Inequalities:If equation 2 = 0 it is an open set?
Kim Reply
or infinite solutions?
The answer is neither. The function, 2 = 0 cannot exist. Hence, the function is undefined.
Embra Reply
if |A| not equal to 0 and order of A is n prove that adj (adj A = |A|
Nancy Reply
rolling four fair dice and getting an even number an all four dice
ramon Reply
Kristine 2*2*2=8
Bridget Reply
Differences Between Laspeyres and Paasche Indices
Emedobi Reply
No. 7x -4y is simplified from 4x + (3y + 3x) -7y
Mary Reply
is it 3×y ?
Joan Reply
J, combine like terms 7x-4y
Bridget Reply
im not good at math so would this help me
Rachael Reply
I'm not good at math so would you help me
what is the problem that i will help you to self with?
how do you translate this in Algebraic Expressions
linda Reply
Need to simplify the expresin. 3/7 (x+y)-1/7 (x-1)=
Crystal Reply
. After 3 months on a diet, Lisa had lost 12% of her original weight. She lost 21 pounds. What was Lisa's original weight?
Chris Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
many many of nanotubes
what is the k.e before it land
what is the function of carbon nanotubes?
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
what is system testing
what is the application of nanotechnology?
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
anybody can imagine what will be happen after 100 years from now in nano tech world
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
silver nanoparticles could handle the job?
not now but maybe in future only AgNP maybe any other nanomaterials
can nanotechnology change the direction of the face of the world
Prasenjit Reply
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
Ali Reply
the Beer law works very well for dilute solutions but fails for very high concentrations. why?
bamidele Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Natural sciences grade 9. OpenStax CNX. Sep 15, 2009 Download for free at http://cnx.org/content/col11069/1.1
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