The cactus family is known for its prickly spines, which are actually altered leaves. The kind of leaves that a maple or oak tree has are not present on cacti. But in the distant past, they might have had leaves that were at least somewhat more similar. Due to the fact that they aid the plants in surviving in hot, dry situations, those leaves eventually changed into the prickly spines we see on cactuses today.
“They could serve as a defensive strategy to prevent herbivores, or animals that consume plants, from consuming the cactus. But spines also produce shade! “Kimberlie McCue says.
“When you are covered with spines, those spines are throwing shadows on the cactus’ body as the sun moves across the sky. They are tiny umbrellas for shade.”
All cacti are native to arid regions, and some can even survive in dry climates. How do they acquire water to exist, then? Kimberlie informs us that these plants can be found close to the water.
“There will be fog coming off the ocean in the morning. Water condenses on those spines, forming tiny droplets, which then flow down the spine, to the plant’s body, to the soil, and to the roots.”
As they hold the soil in place and offer shelter to birds and other creatures, cactuses are also crucial components of their desert ecosystems. In exchange, such animals and birds assist in pollinating the cactus flowers. Cacti are a significant local source of food for people.
Cactuses are unfortunately threatened by people who illegally steal natural plants from their surroundings. According to Kimberlie McCue, being cautious when purchasing cactus plants is one method to ensure that cacti remain healthy and numerous. Before you buy, find out where the cactus came from and confirm that the vendor is being a responsible steward of these plants.
Why does a cactus’ stem have spines?
Cacti have numerous adaptations that enable them to survive in arid climates; these adaptations enable the plant to efficiently gather water, store it for a long time, and conserve it (minimizing water loss from evaporation).
Cacti have thick, succulent stems with rigid walls that store water when it rains. The stems are fleshy, green, and photosynthetic. Either the stem’s inside is spongey or hollow (depending on the cactus). The water inside the cactus is prevented from evaporating by a thick, waxy layer.
Long, fibrous roots are common in cactus, and these roots take moisture from the earth. Some cacti, such as ball cacti, have smaller, more compact roots that can capture dew that falls from the cactus.
Most cacti feature scales or spines in place of leaves (which are modified leaves). These scales and spines do not evaporate their water (unlike regular leaves, which lose a lot of water). Predators (animals that would like to consume the cactus to gain food and/or water) are kept at bay by the spines. On a cactus, areoles are a circular collection of spines. An areole is where flowers bud, and it is also where new stems branch.
How do cactus spines aid in desert survival?
By serving a variety of purposes, spines enable cactus to survive and even thrive in arid settings. They shield the plant from predators, offer shade, aid in temperature control, lessen water loss, and even encourage the plant to spread and procreate.
Why are there spines on plants?
The majority of plants that have spines utilize them to defend themselves against predators, despite evidence to the contrary showing that in several plant groups, such as the cacti, the development of spines was primarily motivated by the need to prevent water loss from leaves.
Why do plants in the desert have spines?
The thorny plants, like cactus, are attractive to look at but difficult to manage because most people are reluctant to admit they would enjoy having one because of the potential for intense discomfort. Cactus, agave, and mesquite are examples of desert plants that must endure in areas with little water. To live, these desert plants must contend with a variety of strange situations.
Other plants lose moisture through the pores on their leaves and stems, which they have. Therefore, in order to lock in the meager amounts of moisture they have, these desert plants must avoid those pores. As a result, these leaves lack pores and develop hard, dry spines or thorns. By not releasing any moisture at all, these thorns save water. The lower, greener portion of a leaf has the least amount of activity, assisting the plant’s survival. To protect themselves from being nibbled on, the spikes also cover the pores.
- They are short because of a slower development mechanism.
- Desert plants must make efficient use of their limited water supply.
- Even still, they develop much more slowly than typical plants do.
As a result, these clever prickly bushes develop slowly while protecting themselves and preserving resources.
Why do Class 6 cactus plants have spines?
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Question 6:
Which plant’s stem, rather than the leaves, performs photosynthesis?
Cactus leaves have been transformed into spines. All of the tasks that would normally be carried out by leaves, including photosynthesis, are carried out by the green stem.
Question 10:
Through transpiration, a plant’s leaves control its water content. Nutrients and water are taken up from the roots as the plant loses water through transpiration.
“A number of thin fibre-like roots coming from the base of the stem” describes what?
A grass plant is defined as having “a number of thin, fiber-like roots emerging from the base of the stem.” Fibrous roots are the name given to these roots.
The ginger plant’s underground fleshy portion is a modified stem that stores food.
Plants with flimsy stems can be supported by these structures, which can be formed from both stems and leaves.
Plants with flimsy stems can benefit from tendrils, which can be formed from both stems and leaves.
Question 11:
Transporting water, minerals, and food is what the veiny network of a leaf does. It also helps to support the leaf.
When a flower is pollinated, pollen grains are moved from the anther to the stigma of the same bloom or to another flower by wind, water, or insects.
From the branches, prop roots extend downward, and once they touch the ground, they firmly anchor themselves to it. They give some plants, like banyan trees, extra support for their massive branches.
Because it produces food for the plant through the process of photosynthesis, the leaf is known as the “food factory” of plants.
Give each of the following’s key purposes:
(a) Root: They draw water and minerals from the soil, giving the plant’s vital nutrition.
(b) Stem: They support the plant’s erect posture. They move food, minerals, and water to all areas of the plant.
(c) Leaf: The preparation of food through photosynthesis is the leaf’s most significant function.
(d) Flower: A flower’s primary purpose is to serve as a site for reproduction. It has both male and female reproductive components, the stamen and pistil.
Cut the base off of a balsam plant. Take some water and a few drops of red ink and combine them in a beaker. For one day, place the plant inside this beaker. Next day, check on the plant. The stem, leaves, and flower petals all have fine red lines that may be seen. This experiment illustrates how plants move water around.
Why are cactus plant leaves changed to have spines? So how does the plant produce food?
Cacti thrive in arid climates with limited water supplies. To stop water loss from the surface of the leaves, cactus leaves have been adapted to become spined. Chlorophyll can be found in the cactus plant’s green stem. As a result, rather than the leaves, the stem serves as the primary site of photosynthesis in cactus plants.
Make a labeled diagram to demonstrate how leaves transpire. How can a plant benefit from transpiration?
More water is drawn in from the roots as water vapour is expelled from the leaves during the transpiration process. More nutrients and minerals are also absorbed by the roots as a result of the water flow.
Create a diagram of a flower’s section with the sepals, petals, stamens, and pistil visible.
The majority of flowers share a similar fundamental structure.
The diagram below can be used to illustrate the structure of a flower:
Question 13:
The anther produces tiny particles that are crucial for reproduction. Mention them.
Pollen grains are the little particles created in the anther. They engage in sexual reproduction.
Question 14:
Even a small mango plant’s stem will be brown and rigid, which typically indicates a trait of a tree stem, hence a small mango plant cannot be classified as a herb. Additionally, this trait shows that the plant is still developing and has not reached full development.
Some flowers are pollinated by the wind rather than by insects. Do you believe these flowers are as beautiful as those that are pollinated by insects?
Flowers that are pollinated by the wind are often tiny, colorless, and odorless. Insects are therefore not drawn to these kinds of flowers. Such blooms will have many, dusty pollen grains that are vast in number and easily swept away by the wind.
The wind-pollinated flowers are less appealing than the insect-pollinated blossoms when the two types of flowers are contrasted.
How is preparing food for you in the kitchen different from preparing food for a plant via a leaf?
Without the need for carbon dioxide or sunlight, we cook our food right in the kitchen. We prepare food in the kitchen using materials that are either derived from plants or animals.
In contrast, plants use photosynthesis, which involves water being absorbed by the roots and carbon dioxide from the air, to create their food.