Plant Stem Types and Features

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Questions and Answers

What is the defining characteristic of a suffruticose stem?

It grows only in tropical regions.

Lower parts are woody, while the upper parts are herbaceous. (correct)

The stem is herbaceous throughout.

It has a completely woody structure.

Which plant structure is identified as having hollow internodes and enlarged nodes?

Climbing stem

Culm (correct)

Creeping stem

Suffruticose stem

Which of the following describes a creeping plant stem?

The main axis grows upright.

It produces vertical shoots exclusively.

The main axis lies along the ground. (correct)

It has a thick woody base.

What is a common example of a suffruticose stem?

Thyme Signup and view all the answers

What term is used to describe a surface that is smooth and free from hair?

Glabrous Signup and view all the answers

Which of the following describes a stem characterized by projections or stiff structures?

Spiny Signup and view all the answers

What distinguishes culm from other types of stems?

It features hollow internodes. Signup and view all the answers

What is the characteristic of a stem that breaks quickly, resulting in a smooth fractured surface?

Short fracture Signup and view all the answers

Which feature would describe a stem that is not smooth and feels uneven or jagged?

Rough Signup and view all the answers

What term describes a stem that has fine lines or wrinkles on its surface?

Striated Signup and view all the answers

What is the morphology of the stem of Hyoscyamus?

Cylindrical, grayish yellow, hairy and hollow Signup and view all the answers

Which characteristic is true about the stem of Lobelia?

It is angular and irregularly furrowed Signup and view all the answers

How do the stems of Hyoscyamus and Lobelia differ?

Hyoscyamus has a cylindrical, hairy stem while Lobelia has an angular, irregularly furrowed stem Signup and view all the answers

What describes the stem of Hyoscyamus in terms of texture?

Hairy and hollow Signup and view all the answers

What morphology does Lobelia's stem exhibit?

Angular and irregularly furrowed Signup and view all the answers

What is the color range of the powder of ergot?

Greyish, blackish-grey to purplish brown Signup and view all the answers

Which of the following describes the odor of powder of ergot?

Disagreeable Signup and view all the answers

How is the taste of powder of ergot characterized?

Disagreeable and oily Signup and view all the answers

Which of the following microscopic characteristics is associated with powder of ergot?

Numerous small unequal rounded cells with thin chitinous walls Signup and view all the answers

What is the texture of the cell walls found in powder of ergot as seen microscopically?

Thin and highly refractive Signup and view all the answers

What is ergotism primarily caused by?

Ingestion of ergotized rye bread Signup and view all the answers

Which type of ergotism is characterized by gangrenous symptoms?

Gangrenous type Signup and view all the answers

Which of the following is NOT a commonly recognized form of epidemic toxicity associated with ergotism?

Hemorrhagic type Signup and view all the answers

What consequence does ergotism result from?

Consuming ergotized grains Signup and view all the answers

In the context of ergotism, what does the term 'epidemic toxicity' refer to?

The effects of consuming ergotized food on a large scale Signup and view all the answers

Study Notes

Stem Types

Suffruticose or shrubby stem: Woody at the base, herbaceous at the top. Example: Thyme.
Culm: Hollow internodes with enlarged nodes. Example: Maize.
Creeping: Main axis of plant lies along the ground.

Stem Surface Features

Glabrous or smooth: No hair or other surface features.
Glossy: Shiny surface.
Rough: Uneven surface.
Hairy: Covered with hairs.
Spiny: Has spines.
Striated or wrinkled: Has lines or grooves on the surface.

Stem Fracture

Short: Breaks easily, leaving a smooth fracture surface.

Hyoscyamus (Henbane)

Stem: Cylindrical, grayish yellow, hairy, and hollow.
Flowering Stage: The stem typically reaches its full length towards the end of flowering.

Lobelia

Stem: Angular, irregularly furrowed.

Ergot (Claviceps purpurea)

Powder: Greyish to purplish brown.
Odor: Disagreeable.
Taste: Disagreeable and oily.
Microscopic Features: Numerous small, unequal, rounded cells with thin, highly refractive chitinous walls.
Toxicity: Ergotism is caused by consuming ergotized rye bread. Two main forms of ergotism are:
- Gangrenous type (St. Anthony's Fire): Characterized by gangrene in the extremities.
- Convulsive type: Causes seizures, hallucinations, and other neurological symptoms.

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Description

This quiz explores various types of plant stems, their surface features, and specific examples such as Hyoscyamus and Lobelia. Test your knowledge on stem characteristics, fractures, and the unique traits of plants such as maize and henbane.