Especialidades JA/Semillas - Avanzado/Respuestas

Semillas - Avanzado

Nivel de destreza

2

Año

1961

Version

05.11.2024

Autoridad de aprobación

Asociación General

1

Tener la especialidad de Semillas.

Para consejos e instrucciones, véase Semillas.

2

Identificar a partir de dibujos y conocer la finalidad de cada una de las siguientes partes de una semilla:

a. Endospermo

b. Radículo

c. Plúmula

d. Micrópilo

Diagram showing the endosperm and radicle.

Plant ovules: Gymnosperm ovule on left, angiosperm ovule (inside ovary) on right

Endosperm

Endosperm is the tissue produced in the seeds of most flowering plants around the time of fertilization. It surrounds the embryo and provides nutrition in the form of starch, though it can also contain oils and protein.

Radicle

The radicle is the first part of a seedling (a growing plant embryo) to emerge from the seed during the process of germination. The radicle is the embryonic root of the plant, and grows downward in the soil.

Plumule

The plumule is the embryonic shoot. It is the precursor to the stem and leaves of the plant.

Micropyle

The micropyle is an opening in a plant's ovule (the structure that gives rise to and contains the female reproductive cells). The micropyle opening allows the pollen tube to enter the ovule for fertilization. In gymnosperms (e.g. conifers), the pollen itself is drawn into the ovule and the micropyle opening closes after pollination. During germination, the seedling's radicle emerges through the micropyle.

3

Conocer varias diferencias entre una semilla monocotiledón y una dicotiledón y dar tres ejemplos de cada una de ellas.

Comparison of a monocot (left) and dicot (right) sprouting

In monocotyledons (or simply monocots), the seed embryo has one cotyledon while the embryo of the dicotyledon (or dicot) has two. The major leaf veins in a monoct are parallel, but they are branched in a dicot. The flower parts (petals, sepals, etc.) in monocots are multiples of three while in dicots are multiples of four or five.

Monocots

• Corn
• Grasses (such as wheat, rye, barley, etc.)
• Lilies
• Onions, garlic

Dicots

• Roses
• Asters
• Nightshades (tomatoes, potatoes, etc.)
• Squash, pumpkin
• Beans

4

Explicar el objetivo y el uso de un probador de semillas (semillas en papel húmedo). Utilizar para probar la germinación de 100 semillas de una planta silvestre y 100 semillas de una planta doméstica. Informar sobre los resultados de cada prueba.

Adventist Youth Honors Answer Book/Germination testing

5

¿En qué se diferencian una semilla de una espora?

A chief difference between spores and seeds as dispersal units is that spores have very little stored food resources compared with seeds, and thus require more favorable conditions in order to successfully germinate. Seeds, therefore, are more resistant to harsh conditions and require less energy to start cell division. Spores are usually produced in large numbers to increase the chance of a spore surviving.

6

Escribir o decir por vía oral dos lecciones espirituales que se pueden aprender a partir de las semillas. Se puede encontrar ayuda en Palabras de Vida del Gran Maestro de Elena G. de White, páginas 16 al 42.

You can read this text online or you can get a copy of the book at The Adventist Book Center.

This text is a discourse on the parable of the sower as found in Matthew 13. Ellen White illustrates several spiritual lessons based on this parable.

7

Hacer una colección de 60 diferentes clases de semillas, de los cuales sólo 15 pueden ser tomadas de paquetes de semillas comerciales, los otros 45 se deben de recolectar por sí mismo. Etiquetar cada clase de la siguiente manera: nombre de la semilla, fecha recolectada, la ubicación donde se recogieron y el nombre del coleccionista.

Adventist Youth Honors Answer Book/Nature/Seeds/Seed collection

8

Tener en su colección cuatro clases de semillas de cada una de las dos familias de plantas que muestra similitud entre las semillas de plantas de cualquier familia única.

The two families of plants are the moncots and the dicots. To see the difference, cut a corn kernel and a bean in half. The corn seed will be difficult to divide, but the bean will almost divide itself in half at the boundary between the two cotyledons.

References