Biology · Environmental Studies

Forestry and Plant Sciences

1,005 Questions

Review important biological concepts with these questions on forestry and plant sciences. The topics include non-timber forest products, timber wood types, lichen growth, and tree structures. This content is ideal for students preparing for agriculture and biology exams.

Industrial wood productionLichen growth patternsNon-timber forest productsPapilionaceous timber woodsTree crown typesFast growing trees

Forestry and Plant Sciences Questions

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

Hockey handle is prepared from the wood of

  1. Salix

  2. Morus

  3. Picea

  4. Phytelephas
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A.Salix  - wood is used in making boxes, brooms, cricket bats, Hockey bats,cradle boards, chairmans and other furniture, dolls, flutes, poles, sweat lodges, toys, turnery, tool handles, veneer, wands and whistles.

B.Morus – wood is used in making Fence posts, furniture, and turned objects

C.Picea – wood is used in buildings

d.Phytelephas – wood is used in making ivory.

So, the correct option is ‘ Salix’.    

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

Wood of Dalbergia consists of

  1. $90-95\%$ vessels
  2. $90-95\%$ tracheids
  3. $50-60\%$ vessels and $40-50\%$ tracheids

  4. Vessels, tracheids and parenchyma in equal proportions
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In Dalbergia, during secondary growth, hart wood is formed. It consists of vessels, trachieds and parenchyma in equal proportions.

So, the correct option is ‘Vessels, trachieds, and parenchyma in equal proportions’.

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

Youngest heartwood is found.

  1. In the centre

  2. Just outside the sapwood

  3. Just inner to sapwood

  4. Just outside the primary xylem
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

In the trunk and older branches of the large trees, only the outer secondary xylem i.e. sapwood serves in water conduction. Whereas the inner part i.e. heartwood,  is composed of dead but structurally strong primary xylem. Thus the youngest layer of secondary xylem is located just inner to sapwood and not in the centre of the stem.

The correct answer is option C.

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

Wood with specific gravity of less than $0.05$ occurs in ___________.

  1. Ochroma

  2. Olea laurifolia

  3. Xylia dolabrifromis

  4. Aeschynomene hispida
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

  • Wood specific gravity is the measurement of the amount of dry cell-wall material per unit volume of the wood. 
  • It is in such a way that probably the single most important predictor of the properties of wood. 
  • It is among the species as woods range in specific gravity from less than 0.05 for Aeschynomene hispida Wild.
  • Thus, the correct answer is option D.

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

Hardness of woody tissue is due to

  1. Silica

  2. Lignin

  3. Cellulose

  4. Suberin
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
  • The hardness of a cell refers to the sturdiness of the cell wall because of the presence of lignin and cellulose present in them.
  • Lignin is a naturally occurring complex organic cross-linked phenolic polymer that forms an important structural material of the plant cell wall (secondary cell wall).
  • They are mainly found regions of wood and bark as they provide rigidity and prevents deterioration.
  • It also provides support to tissues of vascular plants and few algae.
  • So, the correct answer is 'Lignin'.
Multiple choice botany plants in daily life types of wood importance of plants secondary growth in stem

The commercial catch is obtained from the heart wood of

  1. Acacia senegal

  2. Acacia catechu

  3. Acacia arabica

  4. All of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Catch is obtained from the heartwood of Acacia species, especially from Senegalia catechu or Acacia catechu. 

It is used as an astringent, food additive, dye and tannin. 
So the correct option is B.

Multiple choice botany plants in daily life types of wood importance of plants secondary growth in stem
Which of the following statements are correct about heartwood?

(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.

  1. (ii) and (iv)

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

  3. (ii), (iii) and (iv)

  4. (i) and (iv)
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Heartwood is non -functional as it does not conduct water and minerals. It may have ingrowths of tylosis, deposition of resins, tannins and other secondary metabolites of the plant. It is hard and is also called duramen.

So, the correct answer is '(i) and (iv)'

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

Select the correct option:

In (i) porous wood, vessels are very broad in the (ii) wood and are quite narrow in the (iii) wood. This kind of wood is present in (iv) and it translocates (v) amount of water when required by the plant.
Select the correct fill ups for the above paragraph.

  1. (i)-diffuse, (ii)-autumn, (iii)-spring, (iv)-Dalbergiasissoo, (v)-more

  2. (i)-diffuse, (ii)-spring, (iii)-autumn, (iv)-Syzygiumcumini, (v)-less

  3. (i)-ring, (ii)-spring, (iii)-autumn, (iv)-Dalbergiasissoo, (v)-more

  4. (i)-ring, (ii)-autumn, (iii)-spring, (iv)-Syzygiumcumini, (v)-less
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
Due to the presence of vessels, the wood is said to be porous. Vessels present in the spring or earlywood are very large and form conspicuous rings in this wood while those present in the autumn wood or latewood are small or only moderately large. The wood with these characteristics is called ring porous.
This kind of wood present in Dalbergia sissoo( Papilionoideae). It translocates more amount of water when required by the plant.
So, the correct answer is '(i) ring, (ii)- spring, (iii)- autumn, (iv)- Dalbergiasissoo, (v)- more'.
Multiple choice botany plants in daily life types of wood importance of plants secondary growth in stem

Central resin-clogged secondary xylem is?

  1. Central wood

  2. Heartwood

  3. Alburnum

  4. Hardwood
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A.Central wood - The hard fibrous material that forms the main substance of the trunk or branches of a tree or shrub, used for fuel or timber.

B.Heart wood -  The inner or central dark colored non-functional resin clogged wood or secondary xylem formed during secondary growth in dicot stem is called Heart wood or duramen.

C.Alburnum– The outer light coloured functional wood which contains living cells formed during secondary growth in dicot stem is called Alburnum or sap wood.

D.Hardwood – secondary xylem or wood present in broad leaved tropical and temperate forests.

So, the correct option is ‘Heart wood’.

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

Each annual ring or growth ring consists of two strips of.

  1. Antumn wood and spring wood

  2. Heart wood and sap wood

  3. Xylem and phleom

  4. Cork and cortex
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A ring of wood or secondary xylem formed by the association of spring wood and autumn wood is called annual ring. In every year one annual ring formation occurs in dicot stems.

So, the correct option is ‘autumn wood and springwood’.

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

A cut trunk shows $26$ concentric rings of spring wood and autumn wood in alternate rows. The age of trunk would be.

  1. $13$ years
  2. $26$ years
  3. $52$ years
  4. $104$ years
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In dicotyledonous stems, during intra stellar secondary growth, a ring of cambium called vascular cambium is formed.  In the plants growing temperate regions, the activity of vascular cambium is influenced by the existence of maximum seasonal variations. In the spring or early summer, due to the existence of favourable conditions, a large amount of secondary xylem is formed. it is called Springwood or early wood. In the autumn season, due to the presence of unfavourable conditions, less amount of wood is formed. it is called autumn wood or latewood.  Every ring of spring wood and autumn wood together form into an annual ring. In the 26 rings, 13 rings constitute spring wood and 13 rings constitute autumn wood. So total 13 annual rings are present.

So, the correct option is '13 years'.

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

Which of the following is not correct?

  1. Early wood is characterised by a large number of xylary elements

  2. Late wood is characterised by a large number of xylary elements

  3. Early wood is characterised by vessels with narrower cavities

  4. Late wood is characterised by vessels with narrower cavities
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In winter, when the cambium is less active and forms fewer xylary elements that have narrow vessels then this wood is called autumn wood or late wood. While, in spring season, cambium is very active and produces a large number of xylary elements having vessels with wider cavities, this wood is called springwood or early wood.

So, the correct answer is 'Latewood is characterised by a large number of xylary elements'.