Significance Of Secondary Growth | Heart Wood | Sap Wood | Callus | Class 12 Biology (Urdu/Hindi)
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About This Video ........................
In This Video Lecture You Will Learn Basic Concept Of Significance Of Secondary Growth
Signiicance of Secondary Growth
Stem and root often begin to thicken after their apical meristem has produced embryonic or primary
tissue. An increase in plant girth due to vascular cambium and cork cambium is called secondary
growth. The result of secondary growth is most evident in woody perennial plants like trees, shrubs
and vine. Secondary growth occurs due to cell division in : (i) Vascular cambium (ii) Cork cambium.
Vascular cambium irst appears as a cylinder of actively dividing cells between primary xylem and
In most trees, the conduction of water and dissolved substances by secondary xylem become
to the inner surface of the vascular cambium, the other is the secondary phloem appearing outer
primary phloem. Vascular cambium gives rise to two new tissues, one is the secondary xylem next
at the base of trunk indicates the age of a tree at the time it was cut.
rings are active in conduction at one time. The active portion is called sap wood. The inactive non
to the vascular cambium.
In most species, the heartwood accumulates a variety of chemicals such as resins, oils, gums and
conducting wood is called heartwood.
The secondary xylem causes most of the increase in stem thickness. Over the years a woody stem
tannins. These provide a resistance to decay and insect attack, for example, in red cedar and
gets thicker and thicker as its vascular cambium produces layer upon layer of secondary xylem.
These layers are visible as rings. Since one growth ring is formed in one year, a count of the rings
limited to the outer or younger portion of that tissue. As trees grow older only few annual growth
conifers.
About This Channel.....................
I make these videos cause I love to draw and connect the complexity of science and medicine into art. I'm not saying. I'm 100% correct in all my videos, but I do try to obtain the information from credible sources.
One-stop destination for all biology lectures.
_ students in class 11, 12 or appearing for competitive medical exams ( NMDCAT ) will find it very beneficial
_ The videos are categories under various heading to make the students life simplified
Visit My Other Channel Playlist .....................
NMDCAT PART 1: New 1st Year Biology
NMDCAT PART 2: New 2nd Year Biology
Class 11th Lectures: New 1st Year Biology
Class 12th Lectures: New 2nd Year Biology
Class 10th Lectures:
Matric Biology
Subscribe My Channel:
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Social Link........................
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https://instagram.com/ranaalibiologis...
About This Video ........................
In This Video Lecture You Will Learn Basic Concept Of Significance Of Secondary Growth
Signiicance of Secondary Growth
Stem and root often begin to thicken after their apical meristem has produced embryonic or primary
tissue. An increase in plant girth due to vascular cambium and cork cambium is called secondary
growth. The result of secondary growth is most evident in woody perennial plants like trees, shrubs
and vine. Secondary growth occurs due to cell division in : (i) Vascular cambium (ii) Cork cambium.
Vascular cambium irst appears as a cylinder of actively dividing cells between primary xylem and
In most trees, the conduction of water and dissolved substances by secondary xylem become
to the inner surface of the vascular cambium, the other is the secondary phloem appearing outer
primary phloem. Vascular cambium gives rise to two new tissues, one is the secondary xylem next
at the base of trunk indicates the age of a tree at the time it was cut.
rings are active in conduction at one time. The active portion is called sap wood. The inactive non
to the vascular cambium.
In most species, the heartwood accumulates a variety of chemicals such as resins, oils, gums and
conducting wood is called heartwood.
The secondary xylem causes most of the increase in stem thickness. Over the years a woody stem
tannins. These provide a resistance to decay and insect attack, for example, in red cedar and
gets thicker and thicker as its vascular cambium produces layer upon layer of secondary xylem.
These layers are visible as rings. Since one growth ring is formed in one year, a count of the rings
limited to the outer or younger portion of that tissue. As trees grow older only few annual growth
conifers.
About This Channel.....................
I make these videos cause I love to draw and connect the complexity of science and medicine into art. I'm not saying. I'm 100% correct in all my videos, but I do try to obtain the information from credible sources.
One-stop destination for all biology lectures.
_ students in class 11, 12 or appearing for competitive medical exams ( NMDCAT ) will find it very beneficial
_ The videos are categories under various heading to make the students life simplified
Visit My Other Channel Playlist .....................
NMDCAT PART 1: New 1st Year Biology
NMDCAT PART 2: New 2nd Year Biology
Class 11th Lectures: New 1st Year Biology
Class 12th Lectures: New 2nd Year Biology
Class 10th Lectures:
Matric Biology
Subscribe My Channel:
aliacademya7r
Social Link........................
Instagram:
https://instagram.com/ranaalibiologis...
3 سال پیش
در تاریخ 1400/08/23 منتشر شده
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