Tag: botany

Questions Related to botany

Balck wood is obtained from

botany plants in daily life types of wood importance of plants secondary growth in stem

  1. Dalbergia

  2. Albizzia

  3. Manihot

  4. Salvia

Show answer
Correct Option: A
Explanation:
  • Dalbergia is also known as African Blackwood.
  • It is a flowering plant belonging to the family Fabaceae which are native to seasonally dry regions of Africa.
  • It produces dense, lustrous wood which is reddish to pure black in colour.
  • So, the correct answer is 'Dalbergia'.

Out of diffuse porous and ring porous woods, which is correct?

botany plants in daily life types of wood importance of plants secondary growth in stem

  1. Ring porous wood carries more water for short period.

  2. Diffuse porous wood carries more water.

  3. Ring porous wood carries more water when need is higher.

  4. Diffuse porous wood is less specialised but conducts water rapidly throughout.

Show answer
Correct Option: D
Explanation:
  • In ring-porous trees, the vessels laid down at the beginning of the growing season are much larger than subsequent vessels laid down at the end of the season. Diffuse porous trees form the vessel of roughly the same radial diameter throughout the growing season.

So, the correct option is 'Diffuse porous wood is less specialized but conducts water rapidly throughout'

Spring wood is $\underline{(a)}$ in colour & has $\underline{(b)}$ density as compared to heart wood.

botany plants in daily life types of wood importance of plants secondary growth in stem

  1. (a)-Darker, (b)-Heavier

  2. (a)-Lighter, (b)-Lower

  3. (a)-Darker, (b)-Lower

  4. (a)-Lighter, (b)-Heavier

Show answer
Correct Option: B
Explanation:

Springwood is formed due to the rapid activity of the vascular cambium. The vessels are wider in lumen. It is light and has low density. Heartwood is the wood that has non-functional vessels due to deposition of lignin by tyloses. It appears dark and has more density. So, the correct answer is springwood is lighter in colour and has a lower density as compared to heartwood.

Match column i with column - ii and select the correct answer.

Coloumn-1 Column-2
A Spring wood  Duramen
B Autumn wood  Alburnum
c Heart wood  Late wood 
d Sap wood  Early wood 
botany plants in daily life types of wood importance of plants secondary growth in stem

  1. A - (iv), B - (iii), C -(i) , D - (ii)

  2. A -(iii), B -(iv), C- (ii) , D-(ii)

  3. A - (iii), B - (iv), C-(i) , D-(ii)

  4. A-(iii), B - (iv) , (ii) , D-(i)

Show answer
Correct Option: A
Explanation:

A. Springwood is the soft and porous portion of an annual ring of wood developed during the early growing season or spring season and is known as earlywood.

B. Autumn wood constitutes a narrow strip in the annual ring formed during the winter season and are dark in colour with high density, it is also known as latewood.
C. Heartwood is the dead, central part in the wood of trees, the cells usually contain tannins and are also known as duramen.
D. Sapwood is the outer, living layers of the wood of trees that can transport water and minerals to the crown of the tree and is also known as alburnum.
So, the correct answer is 'A - (iV), B - (iii), C -(i) , D - (ii)'.

Which of the following statements are correct about heart wood? 
i) It does not help in water conduction.
ii) It is also called alburnum.
iii) It is light in colour and is very soft
iv) It has tracheary elements which are filled with tannins, resins,etc.

botany plants in daily life types of wood importance of plants secondary growth in stem

  1. (ii) and (iv)

  2. (i), (ii) and (iii)

  3. (i) and (iv)

  4. None of the above

Show answer
Correct Option: C
Explanation:
  • Heartwood is also known as duramen.
  • It is the central dead part wood of trees. 
  • The cells in this region contain tannins or resins that give it a dark colour.
  • It is inactive and does not conduct water.
  • So, the correct answer is '(i) and (iv)'.

Alburnum is also called as 

botany plants in daily life types of wood importance of plants secondary growth in stem

  1. Autmn wood

  2. Heart wood

  3. Sap wood

  4. Spring wood

Show answer
Correct Option: C
Explanation:
  • The outer, new living layers of a secondary wood of a tree where transport of water and minerals to the crown of the tree take place are called alburnum. 
  • Alburnum is also known as sapwood.
  • It contains high moisture content than a heartwood.
  • So, the correct answer is 'Sapwood'.

Heart wood provides?

botany plants in daily life types of wood importance of plants secondary growth in stem

  1. Mechanical strength only

  2. Facilities for storage of food materials

  3. Pathway for ascent of sap

  4. Buoyancy

Show answer
Correct Option: A

The wood is actually a?

botany plants in daily life types of wood importance of plants secondary growth in stem

  1. Secondary xylem

  2. Secondary phloem

  3. Primary xylem

  4. Primary phloem

Show answer
Correct Option: A

Diffuse porous woods are characteristic of plants growing in ________________.

botany plants in daily life types of wood importance of plants secondary growth in stem

  1. Alpine region

  2. Cold winter regions

  3. Temperate climate

  4. Tropical

Show answer
Correct Option: D
Explanation:

In most of the gymnosperms such as conifers and cycads. Vessels are not present and the wood is made entirely of tracheids. These woods are known as nonporous. In angiosperms, the wood consists of both tracheids and vessels. The wide vessels are appearing with pores between. Such wood is called porous. 

In these porous woods, if vessels have essentially equal diameters the wood is known as diffuse-porous. It is the characteristic of plants growing in tropical regions.

So, the correct option is D.

Heartwood differs from sapwood in ____________________.

botany plants in daily life types of wood importance of plants secondary growth in stem

  1. Absence of vessels and parenchyma

  2. Having dead and non-conducting elements

  3. Being susceptible to pests and pathogens

  4. Presence of rays and fibers

Show answer
Correct Option: B
Explanation:

The older woody trees show two characteristic types of wood namely heartwood and sapwood. The heartwood is made up of dead xylem vessels that have been filled with tyloses and are rich in deposits of resins and tannins. These are non-functional and appear darker. 

The sapwood contains the newly formed vessels that are functional and appear lighter. The hardwood provides resistance from the pest attack and increases the durability of the wood.

Hence, the correct answer will be having dead and non-conducting elements.

The correct option is B.