Home
Class 12
BIOLOGY
Shoot apex forms lateral branches of ste...

Shoot apex forms lateral branches of stem, leaves and
(a) Is unidirectional in activity
(b) Is present just above youngest leaf primordia
(c ) Does not show plastochron periodicity
(d) Shows subterminal position

A

(a) and (b) are correct

B

Only (d) is incorrect

C

(a), (b) and (c ) are correct

D

(c ) and (d) are correct

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question regarding the characteristics of the shoot apex, let's analyze each option step by step: ### Step 1: Understanding the Shoot Apex The shoot apex is a type of apical meristem located at the tip of the shoot. It is responsible for the growth of new leaves, lateral branches, and stems. ### Step 2: Analyzing Option (a) **Option (a): Is unidirectional in activity.** - The shoot apex grows in one direction, typically upwards. This means it elongates in a single direction rather than branching out in multiple directions simultaneously. - **Conclusion:** This statement is correct. ### Step 3: Analyzing Option (b) **Option (b): Is present just above youngest leaf primordia.** - The shoot apex is indeed located at the top of the plant, just above the youngest leaf primordia, which are the early stages of leaf development. - **Conclusion:** This statement is correct. ### Step 4: Analyzing Option (c) **Option (c): Does not show plastochron periodicity.** - Plastochron periodicity refers to the time interval between the formation of successive leaves. The shoot apex does exhibit plastochron periodicity as it regulates leaf formation and development. - **Conclusion:** This statement is incorrect. ### Step 5: Analyzing Option (d) **Option (d): Shows subterminal position.** - The shoot apex is located at the terminal position of the shoot, not subterminal. Subterminal would imply a position below the very top, which is not the case for the shoot apex. - **Conclusion:** This statement is incorrect. ### Final Conclusion The correct options are (a) and (b). Therefore, the shoot apex is unidirectional in activity and is present just above the youngest leaf primordia.
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • ANATOMY OF FLOWERING PLANTS

    VMC MODULES ENGLISH|Exercise IMPECCABLE|59 Videos

  • ANATOMY OF FLOWERING PLANTS

    VMC MODULES ENGLISH|Exercise ENABLE|50 Videos

  • BIODIVERSITY AND CONSERVATION

    VMC MODULES ENGLISH|Exercise IN-CHAPTER EXERCISE-B|10 Videos

Similar Questions

Explore conceptually related problems

Which of the following is not a characteristic features of meristematic cell ? (a) Is shows the ability to divide actively . (b) More than one vacuole is present . (c) It shows prominent nucleus and abundant cytoplasm. (d) The meristematic cell has a thin cell wall due to presence of only cellulose.

An element X which is a yellow solid at room temperature shows catenation and allotropy. X forms two oxides which are also formed during the thermal decomposition of ferrous sulphate crystals and are the major air pollutants (a) Identify the element X (b) Write the electronic configuration of X (c) Write the balanced chemical equation for the thermal decomposition of ferrous sulphate crystals ? (d) What would be the nature (acidic/basic) of oxides formed ? (e) Locate the position of the element in the modern periodic table.

(a) Electropositive nature of the element(s) increases down the group and decreases across the period (b) Electronegativity of the element decreases down the group and increases across the period (c) Atomic size increase down the group and decreases across a period (left to right) (d) Metallic character increases down the group and decreases across a period On the basis of the above trends of the periodic table, answer the following about the electron with atomic number 3 to 9 (a) Name the most electropositive element among them (b) Name the most electronegative element (c) Name of the element with smallest atomic size (d) Name the element which is a metalloid (e) Name the element which shows maximum valency.

Consider the following statements : (a) In leguminous plants, leaf base becomes swollen, called pulvinus (b) The fleshy leaves of Onion and Garlic store food (c) The buds in Australian acacia become green and synthesise food (d) In Alstonia, leaves show alternate phyllotaxy. Of the above statements

The A leaves the eye and the retinal blood vessels enter it at a point medial to and slightly above the posterior pole of the eyeball. B is not present in that region and hence it is called the C . At the posterior pole of the eye lateral to the C there is a yellowish pigmented spot called D with a central pit called the E

It is observed that deficiency of a particular element showed its symptoms initially in older leaves and then in younger leaves. (a) Does it indicate that the element is actively mobilised or relatively immobile ? (b) Name two elements which are highly mobile and two which are relatively immobile. (c) How is the aspect of mobility of elements important to horticulture and agriculture ?

In brief state what happens when (a) Dry apricots are left for sometime in pure water and later transferred to sugar solution? (b) A red blood cell is kept in concentrated saline solution? (c) The plasma-membrane of a cell breaks down? (d) When Rheo leaves are boiled in water first and then a drop of sugar syrup is put on it, osmosis does not occurs, due to the death of the cells of the leaf. This shown that selective permeability is property of living plasma membrane. (e) Golgi complex helps in the package, storage and transfer of proteins synthesised by ribosomes. Thus, when ribosomes are removed the cell will not function properly.

Consider the statements with respect to fungi (a) They show a great diversity in morphology (b) White spots seen on Mustard leaves are due to a saprophytic fungus (c )They prefer to grow in cold and humid places (d) The call walls of fungi are composed of chitin and polysaccharides . Of the above stetements

What is common between the muscle fibers of extensor of human back and those of flight muscles of the birds which remain in flight for long periods of time ? a. They are thinner , red colored b, they are thicker and light colored . c. they have abundant mitochondria . d. they have well developed sarcoplasmic reticulum e. they show rate of contractions for longer periods f, They show fast strenuous activity g. They do not get fatigued early . h. They get fatigued quickly .

An organic acid (A), C_(5)H_(10)O_(2) reacts with Br_(2) in the presence of phosphorous to give (B). Compound (B) contains an asymmetric carbon atom and yield (C) on dehydrabromination. Compound (C) does not show geometric isomerism and on decarboxylation give an alkene (D) which on ozonolysis gives (E) and (F), compound (E) gives a positive schiff's test but (F) does not. Give structures of (A) to (F) with reasons.

Home
Profile