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just water usage? - I also wondered this but obtained the investigation elsewhere so don’ t know. I thought perhaps the plant does not put onthat much mass compared to the mass of the water so it becomes insignificant

Dicotyledonous stem

  • Leaves develop from the nodes.
  • The sections of stem between the nodes are called internodes.
  • An axillary bud is often found at the node. These forms lateral branches.
  • A terminal bud is found at the tip of the stem and allows the stem to increase in length.

Internal structure of the dicotyledonous stem

This diagram of a cross section shows the internal structure of a young dicot stem

  • A waterproof cuticle is found on the outside of the epidermis to prevent water loss.
  • The epidermis consists of a single layer of cells to protect the underlying tissue.
  • The cortex is made up of parenchyma cells that stores water and food.
  • The vascular bundles are arranged in a ring in the medulla and are surrounded by non-living sclerenchyma cells for strengthening and support.
  • Each vascular bundle contains the following:
    • Cambium (contains meristematic cells that divide to widen the stem)
    • Phloem (transports food from leaves to the roots)
    • Xylem (transports water from the roots to the stem)

http://bcs.whfreeman.com/thelifewire/content/ch p36/36020.html

This is a link to an online tutorial about phloem, xylem and pressure flow.

Movement of water up the stem

  • Water moves up the xylem from the roots to the leaves.
  • Adaptations of xylem for transporting water:
    • Long, elongated tubes joined end-to-end without any cross-walls, forming good conducting tubes.
    • The cell walls are thickened with lignin for support (annual or spiral thickening) so that they do not collapse due to the upward pull of water
    • Pitted vessels and tracheids allow for lateral movement of water into neighbouring xylem vessels.
    • Cells are dead, so there is no obstruction to water transport

Diagram of xylem

Three forces are responsible for the movement of water up the xylem – capillarity, root pressure and transpiration suction force.

  • Capillarity involves forces of cohesion (forces of attraction between water molecules) and adhesion (forces of attraction between water molecules and thesides of the xylem vessels). Because the xylem’s lumen (opening) is so tiny, water will move up by capillary. However, this force is weak and its rolein moving water up the stem is small.
  • Root pressure is a force that pushes water up the xylem. As water enters the root by osmosis, it pushes the water that is already in the xylem of the stemupwards.
  • Transpiration suction force is a very important force that pulls water up the xylem of the stem. As water evaporates from the stomata of the leaves duringtranspiration, it creates a sucking force that will pull the water up the xylem.

Investigation: plant tissue anatomy (root and stem)

Aim: To examine the structure of the root and stem

Apparatus

  • Scalpel or knife
  • Celery stalk (stem)
  • Carrot (root)
  • Glass slide
  • Iodine solution (Stain) or water
  • Cover slip
  • Dissecting needle or tweezers
  • Paper and pencil

Questions & Answers

what is microbiologist
Muhammad Reply
what is errata
Muhammad
is the branch of biology that deals with the study of microorganisms.
Ntefuni Reply
What is microbiology
Mercy Reply
studies of microbes
Louisiaste
when we takee the specimen which lumbar,spin,
Ziyad Reply
How bacteria create energy to survive?
Muhamad Reply
Bacteria doesn't produce energy they are dependent upon their substrate in case of lack of nutrients they are able to make spores which helps them to sustain in harsh environments
_Adnan
But not all bacteria make spores, l mean Eukaryotic cells have Mitochondria which acts as powerhouse for them, since bacteria don't have it, what is the substitution for it?
Muhamad
they make spores
Louisiaste
what is sporadic nd endemic, epidemic
Aminu Reply
the significance of food webs for disease transmission
Abreham
food webs brings about an infection as an individual depends on number of diseased foods or carriers dully.
Mark
explain assimilatory nitrate reduction
Esinniobiwa Reply
Assimilatory nitrate reduction is a process that occurs in some microorganisms, such as bacteria and archaea, in which nitrate (NO3-) is reduced to nitrite (NO2-), and then further reduced to ammonia (NH3).
Elkana
This process is called assimilatory nitrate reduction because the nitrogen that is produced is incorporated in the cells of microorganisms where it can be used in the synthesis of amino acids and other nitrogen products
Elkana
Examples of thermophilic organisms
Shu Reply
Give Examples of thermophilic organisms
Shu
advantages of normal Flora to the host
Micheal Reply
Prevent foreign microbes to the host
Abubakar
they provide healthier benefits to their hosts
ayesha
They are friends to host only when Host immune system is strong and become enemies when the host immune system is weakened . very bad relationship!
Mark
what is cell
faisal Reply
cell is the smallest unit of life
Fauziya
cell is the smallest unit of life
Akanni
ok
Innocent
cell is the structural and functional unit of life
Hasan
is the fundamental units of Life
Musa
what are emergency diseases
Micheal Reply
There are nothing like emergency disease but there are some common medical emergency which can occur simultaneously like Bleeding,heart attack,Breathing difficulties,severe pain heart stock.Hope you will get my point .Have a nice day ❣️
_Adnan
define infection ,prevention and control
Innocent
I think infection prevention and control is the avoidance of all things we do that gives out break of infections and promotion of health practices that promote life
Lubega
Heyy Lubega hussein where are u from?
_Adnan
en français
Adama
which site have a normal flora
ESTHER Reply
Many sites of the body have it Skin Nasal cavity Oral cavity Gastro intestinal tract
Safaa
skin
Asiina
skin,Oral,Nasal,GIt
Sadik
How can Commensal can Bacteria change into pathogen?
Sadik
How can Commensal Bacteria change into pathogen?
Sadik
all
Tesfaye
by fussion
Asiina
what are the advantages of normal Flora to the host
Micheal
what are the ways of control and prevention of nosocomial infection in the hospital
Micheal
what is inflammation
Shelly Reply
part of a tissue or an organ being wounded or bruised.
Wilfred
what term is used to name and classify microorganisms?
Micheal Reply
Binomial nomenclature
adeolu
what's microbiome?
john Reply
Microbiology is the scientific study of microorganisms
Ibra
the microorganisms in a particular environment (including the body or a part of the body).
Ibra
describe the bacterial cell
Akello
The biggest populations of microbes reside in the gut.other popular habitats include the skin genitals.The microbial cells and their genetic material ,the microbiome ,live with human from birth .
Zahreen
can agriculture be integrated into biology
David
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Source:  OpenStax, Siyavula: life sciences grade 10. OpenStax CNX. Apr 11, 2012 Download for free at http://cnx.org/content/col11410/1.3
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