AY Honors/Seeds/Answer Key/pt-br

Sementes

Nível de Habilidade

1

Ano

1961

Version

12.11.2025

Autoridade de Aprovação

Conferência Geral

1

Qual o principal objetivo de uma semente?

2

Que alimentos foram dados primeiramente ao homem no Jardim do Éden?

Then God said, "I give you every seed-bearing plant on the face of the whole earth and every tree that has fruit with seed in it. They will be yours for food. Genesis 1:29

3

Identificar a partir de uma semente, ou desenho da mesma, e saber o propósito dos seguintes: tegumento, cotilédone e embrião (germe).

Parts of a seed

• Seed Coat - The seed coat is the covering which encloses the seed (small embryonic plant, usually with some stored food).
• Cotyledon - This is a significant part of the embryo within the seed of a plant. Upon germination, the cotyledon becomes the embryonic first leaves of a seedling.
• Embryo - A seed embryo includes the cotyledon which becomes the plant's first leaves, the epicotyl (not shown), which becomes the shoot above the leaves, the hypocotyl which becomes the plant's stem, and the radicle which becomes the plant's root.

4

Conhecer 4 diferentes métodos pelos quais as sementes são dispersadas pelas plantas. Mencionar 3 exemplos de plantas que espalham suas sementes por cada método.

Gravity

The effect of gravity on the dispersal of seeds and spores is straightforward. Heavier seeds will tend to drop downward from the parent plant, and not by themselves travel very far. Spores, being much lighter, are more influenced by physical movements in the environment, especially those of wind and water, and therefore less strictly subject to the simple motion of gravity (see examples below). Gravity may be sufficient agent for plants growing on steep slopes, but upslope movement of a population can be a problem. The naked seeds of gymnosperms are largely dependent upon gravity for dispersal. Most conifers are long-lived large shrubs or tall trees, thus taking full advantage of gravitational dispersal and allowing for gradual upslope movement of a population. Dispersal of seeds "strictly" by gravity should not overlook storm effects: seeds from a deteriorating cone growing high on a tall, narrow tree will get spread widely during a wind storm (see "Wind" below).

• The coconut produces a large, dry, fiber-filled fruit capable of a long survival adrift at sea.
• Alexandrian laurel or kamani produces a globose fruit that is almost cork-like.

Animals

A barbed seed caught in the fur of a cat.

Seeds are often the bane of bushwalkers

A significant aspect of plant-animal cooperation involves plants designed to take advantage of animal abilities to move. Some fruit have prickly burrs or spikes that attach themselves to a passing animal's fur or feathers so that the animal will carry them away. Some seeds are contained within a soft fruit that "invites" animals to consume it. These seeds have a tough protective outer-coating so that while the fruit is digested, the seeds will pass through their host's digestive tract intact, and grow wherever they fall. Some seeds are appealing to rodents (such as squirrels) who hoard them in hidden caches, often beneath the surface of the soil, in order to avoid starving during the winter and early spring. Those seeds that are left uneaten have the chance to germinate and grow into a new plant.

Some animals that disperse may also eat the seed.

• Beggarlice
• Cockle burr
• Apple
• Banana
• Strawberry
• Oak (acorns)

5

Conhecer 10 tipos de sementes que usamos como alimento.

This list does not include the dozens of seeds used as spices or oil (see below), nor does it include seeds which are incidentally eaten as part of a fruit (strawberry, banana). However, you should accept such answers if they are given.

1. Almond
2. Barley
3. Brazil nut
4. Cashew
5. Chestnut
6. Chickpea (garbanzo)
7. Cocoa
8. Coconut
9. Corn
10. Cowpea
11. Filbert
12. Green bean
13. Lentil
14. Lima bean
15. Macadamia
16. Millet
17. Mustard
18. Navy bean
19. Oat
20. Pea
21. Peanut
22. Pecan
23. Pine nut
24. Pinto bean
25. Pistachio
26. Pomegranate
27. Pumpkin
28. Rice
29. Rye
30. Sesame
31. Soybean
32. Sunflower
33. Walnut
34. Wheat
35. White bean

6

Conhecer 5 tipos de sementes que são usadas como fonte de óleo.

1. Coconut
2. Corn
3. Cottonseed
4. Canola oil (a variety of rapeseed oil)
5. Olive
6. Palm
7. Peanut
8. Safflower
9. Sesame
10. Soybean
11. Sunflower
12. Rice Bran

7

Conhecer 5 tipos de sementes que são usadas como condimentos.

1. Anise
2. Caraway
3. Cardamom
4. Cocoa
5. Coriander
6. Cumin
7. Dill
8. Fennel
9. Nutmeg
10. Mustard
11. Vanilla

8

Qual fator não pode faltar para que uma planta germine?

Requirements for seed germination

Seed germination depends on many factors, both internal and external. The most important external factors include: water, oxygen, temperature, and the correct soil conditions. Every variety of seed requires a different set of variables for successful germination. This depends greatly on the individual seed variety and is closely linked to the ecological conditions in the plants' natural habitat.

Water

Germination requires moist conditions. Mature seeds are usually very dry and need to take up significant amounts of water before they can "come back to life." The uptake of water into seeds leads to a marked swelling. The pressure caused by water aids in cracking the seed coat for germination. When seeds are formed, most plants store large amounts of food, such as starch, proteins, or oils, for the embryo inside the seed. When the seed absorbs water, it breaks down these stored food resources and allows the seedling to germinate and grow until it reaches the light. Once the seedling starts growing, it requires a continuous supply of water and nutrients.

Oxygen

Most seeds respond best when water levels are enough to moisten the seeds but not soak them, and when oxygen is readily available. Once the seed coat is cracked, the germinating seedling requires oxygen. If the soil is waterlogged, it might cut off the necessary oxygen supply and prevent the seed from germinating.

Temperature and light

Seeds germinate over a wide range of temperatures, with many preferring temperatures slightly higher than room-temperature. Often, seeds have a set temperature range for sprouting and will not sprout above or below a certain temperature. In addition, some seeds may require exposure to light or to cold temperature to break dormancy before they can germinate. As long as the seed is in its dormant state, it will not germinate even if conditions are favorable. For example, seeds requiring the cold of winter are inhibited from germinating if they never experience frost. Some seeds will only germinate when temperatures reach hundreds of degrees, as during a forest fire. Without fire, they are unable to crack their seed coats. Many seeds in forest settings will not germinate until an opening in the canopy allows then to receive sufficient light for the growing seedling.

Stratification

Malted (germinated) barley grains

Seeds must be mature and environmental factors must be favorable before germination can take place. When a mature seed is placed under favorable conditions and fails to germinate, it is said to be dormant. Some seeds will not germinate (begin to grow) until they have been dormant for a while. The length of time plant seeds remain dormant can be reduced or eliminated by a simple seed treatment called stratification. Seeds should be planted promptly after stratification.

Stratification mimics natural processes that weaken the seed coat before germination. In nature, some seeds require particular conditions to germinate, such as the heat of a fire (e.g., many Australian native plants), or soaking in a body of water for a long period of time. Others have to be passed through an animal's digestive tract to weaken the seed coat and enable germination.

9

Fazer uma coleção de 30 diferentes tipos de sementes, 20 das quais tenham sido encontradas por você mesmo. Identificar cada uma com o nome, data e local em que foi encontrada, e nome da pessoa que a encontrou. Você poderá colá-las em um papel cartolina ou cartão, ou colocá-las em frascos transparentes.

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

References

• Wikipedia articles
  • Seeds
  • Germination
  • Biological dispersion