Some questions about botany for First Year College students

Question

1. Can you predict the type of placentation a certain fruit will have if you can see only the flower? Why or why not?

2. Drupes are also called stone fruits. Can you explain why?

3. Some commonly called "nuts" are not botanically nuts. Can you give some examples?

4. Why are some fruits also called vegetables?

5. What can be deduced from the relative age of organ showing the first sign of deficiency for a given nutrient?

6. Why are dark colored containers preferably used in culture solution studies?

7. Give examples of plants that have been grown using hydroponics (not necessarily in the Philippines).

8. Soil-less agriculture is practiced extensively in Israel. Why do you think so?

9. Why is cutting of stem under water always done?

10. What are some of the environmental factors which influence the rate of transpiration?

11. What are the pores called through which water escapes from the leaf by guttation?

12. Discuss the advantages and disadvantages of the transpiration process in plants.

13. What strategies have evolved by which plants are able to reduce their transpiration rates and thus conserve water?

14. Explain the statement: “A seed is a baby plant in a box with its own lunch.”

15. Do all dicot seeds have endosperm? Explain your answer.

PLEASE HELP ME BY ANSWERING THESE QUESTIONS. HOPE U CONTRIBUTE. THANK YOU. TC ^_^

Answer 1

1. The placement of the placenta is based on the type of gynoecium that is present. The gynoecium, the collective term for all the carpels, is the innermost whorl of the parts of a flower, and in many flowers the other parts (sepals, petals, and stamens) are attached to the receptacle beneath the gynoecium. In such cases, where the ovary lies above the attachments of the other distinct floral parts, the flower is described as hypogynous or as having a superior ovary. In some species (examples include plum, cherry, and blackberry), the other (noncarpellary) floral parts are fused to form a cup called a floral tube or hypanthium. In these flowers, the ovary lies physically lower than the lobes of the sepals and petals and below the point of attachment of the stamen filaments — the ovary is still considered to be superior but the flower is termed perigynous.

In those flowers in which the floral tube is fused with the ovary, the sepals, petals, and stamens appear to grow out from the top of the ovary, and the flower is said to be epigynous and have an inferior ovary. Examples of plant families with inferior ovaries include orchid, sunflower, and cactus. The position of the ovary is an important consideration in the identification and classification of plant species, as well as the kind of fruit that develops after fertilization.

2. Drupes contain seeds encased in a very hard, stone-like shell (in fact, it can only be opened by smashing or acid treatment). Peaches, cherries, plums are examples of trees which have drupe fruits.

3. A peanut is not a true nut.  It is a legume, as it is a member of the pea family.

4. Some fruits are considered to be vegetables because they are culinarily used as a vegetable (i.e. seasoned with salt instead of sugar).  Examples include tomatoes, squashes, cucumbers, peppers, and eggplant, among others.  (In reverse, rhubarb is a vegetable that is used like a fruit.)

5.  It shows the mobility of the nutrient.   Old leaves show a deficiency in mobile nutrients (like N) while new leaves show a deficiency in immobile nutrients (like Ca).

6. The dark coloration is to block out light from roots that are growing in the solution.

7. Tomatoes, cucumbers, peppers, strawberries.

8. In 1948, when Israel gained independence, this new country of only about 8,100 square miles--about the size of Massachusetts--faced the problem of feeding its people. Over 60 percent of the available land was in the Negev Desert and was classified as either hyperarid, arid, and semiarid. They needed water to grow food. To compensate for this, they went full-scale into hydroponics in glass houses.  Today, Israel produces 95 percent of its own food, importing only grain, oil seeds, meat, coffee, cocoa, and sugar. Since 1948, the area under cultivation has increased from 408,000 acres (74,000 irrigated) to 1.07 million acres (460,000 irrigated) because of hydroponic/glasshouse usage.

9. The xylem tissues are constantly pulling up water as part of the osmotic pressure in the plant.  If a stem is not cut under water, air bubbles form in the stem.  This causes drying of the vascular tissues and speeds up the death of the cutting.

10. Temperature, solar radiation, relative humidity, soil moisture, and water pressure in the plant.

11. hydrathodes

12. Advantages of Transpiration:-

(1) Ascent of sap:Transpiration developes tension in the water column which makes it possible for the water to rise from the xylem of the roots to the top of the plant.

(2) Removal of excess water : Plants absorb far more water than is actully required by the plants.Transpiration helps in removing this excess water.

(3) Absorption & distribution of salts: The rate of salt absorption increases with the rate of transpiration.

(4) Cooling effect:- Sunlight that falls on the leaf can raises the leaf temprature by 30-40 degree centigrade above the atmospheric temperature,and thus harm the leaf tissues.A major portion of this energy is dissipated by transpiration when the water evaporates leading to a cooling effect..

(5) Development of root system: Transpiration allows extensive development of the root system that supports the heavy aerial growth against storms & allows absorption of mineral salts & water.

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Disadvantages

(1) Reduces photosynthesis: Under conditions of water scarcity the rate of photosynthesis decreases. it is due to closure of stomata resulting in non-supply of carbondioxide, & loss of turgidity by the cells.

(2) Reduces growth: all expansion & elongation requires turgidity.

(3) Reduces yield: Water deficit leads 2 wilting & low gtowth . no new leaves r formed. stems & roots lose their meristematic activity.

(4) Fall in metabolism: The protoplasm requires a certain optimum hydration for maximum efficiency.

13. C4 plants have a competitive advantage over plants possessing the more common C3 carbon fixation pathway under conditions of drought, high temperatures and nitrogen or carbon dioxide limitation. 97% of the water taken up by C3 plants is lost through transpiration,compared to a much lower[quantify] proportion in C4 plants, demonstrating their advantage in a dry environment.

CAM plants open their stomata during the cooler and more humid night-time hours, permitting the uptake of carbon dioxide with the minimum water loss.

The carbon dioxide is converted to soluble molecules, which can be readily stored by the plant at a sensible concentration.

The precise chemical pathway involves a three-carbon compound phosphoenolpyruvate (PEP), to which a CO2 molecule is added via carboxylation - forming a new molecule, oxaloacetate. This is then reduced, forming malate. Oxaloacetate and malate are built around a skeleton of four carbons - hence the term C4. Malate can be readily stored by the plant in vacuoles within individual cells.

The next day, malate can be broken down on demand, releasing a molecule of CO2 as it is converted to pyruvate. The pyruvate can be phosphorylated (i.e. have a phosphate group added by the "energy carrier" ATP) to regenerate the PEP with which we started, ready to be spurred into action the next night. But it is the release of CO2 that makes the cycle worth the plant's while. It is directed to the stroma of chloroplasts: the sites at which photosynthesis is most active. There, it is provided to RuBisCO in great concentrations, increasing the efficiency of the molecule, and therefore producing more sugars per unit photosynthesis.

14. Seeds are comprised of an embryo that drives its food from the nutrient-rich cotyledons. These will feed the developing plant until it is large enough to make enough food on its own.

15.  The dust-like seeds of orchids have no endosperm. Orchid seedlings are mycoheterotrophic in their early development. In some other species, such as coffee, the endosperm also does not develop. Instead the nucellus produces a nutritive tissue termed perisperm.

Hope that helps you out!

Answer 2

Here's a few answers:

2. Drupes are also called stone fruits. Can you explain why?

Drupes contain seeds encased in a very hard shell. Peaches, cherries and almonds are examples of trees which have drupe fruits.

3. Some commonly called "nuts" are not botanically nuts. Can you give some examples?

I don't think peanuts are actually classified as nuts. They are a kind of seed called an "achne" (check the spelling!)

4. Why are some fruits also called vegetables?

probably because they don't grow on trees. Tomatoes, watermellons and ocra are technically fruits.

7. Give examples of plants that have been grown using hydroponics (not necessarily in the Philippines).

in New Zealand, hydropinic tomatoes growing in greenhouses are the major source of this "vegetable". This is because new Zealand is too cold to grow tomatoes outdoors and this island has a lot of geothermal energy to heat greenhouses and produce electricity for indoor lighting.

8. Soil-less agriculture is practiced extensively in Israel. Why do you think so?

the soil is probably too salty due to overwatering. when desert soils are irrigated, it draws underground salt deposits to the surface. in Australia wheat fields contain open salt deposits which makes agriculture impossible.

9. Why is cutting of stem under water always done?

This prevents the vascular system from getting air into it. plants use cappilary action as one way of drawing moisture up the stem and this requires an unbroken column of water from bottom to top.

10. What are some of the environmental factors which influence the rate of transpiration?

relative humidity and soil moisture.

11. What are the pores called through which water escapes from the leaf by guttation?

stomata, probably

12. Discuss the advantages and disadvantages of the transpiration process in plants.

transpiration involves a vascular system to transport water and nutrients from the roots to the leaves. Land living plants overcame the force of gravity by thickening their vascular bundles, allowing the to grow taller as they competed for light. Animals developed bones in a similar fashion to overcome the force of gravity on dry land. The disadvantage of a vascular system is the fact this is the plant's only source of water. Unlike water plants, land plants have a thick epidermis and can't absorb water directly through their skins like marine algae can do in the ocean.

13. What strategies have evolved by which plants are able to reduce their transpiration rates and thus conserve water?

CAM metabolism is the most sophisticated and successful aproach. Plants manufacture sugar by opening their stomata and allowing CO2 into the leaf. It is then combined with water to form simple carbohydrates using solar energy. CAM plants only open their stomata at night. The CO2 is turned into a simple organic acid and the process of sugar production stops at this point. When the sun rises, the CAM plant closes its stomata and then uses photosynthesis to complete the transformation of the acids into carbohydrates like glucose and cellulose. Closing the stomata during the hottest part of the day helps prevent water loss.

14. Explain the statement: “A seed is a baby plant in a box with its own lunch.”

Seeds are plant embryos with usually have a source of food in leaf like appendages called cotyledons. These "seed leaves" feed the embryo when it germinates until it develops true leaves. Monocots have 1 cotyledon and dicots have two.

hope this helps!

Answer 3

8. They have been farming there for over 2000 years and the soil is very poor for sustaining plant life as most of the nutrients have been removed.

11. Hydathodes

Answer 4

2. A drupe is called a stone fruit because of the hard stone likee part in the center surrounding the seed.(ex. peach, plum)

3. Some "nuts" are actually drupes because they have an outer green, fleshy husk, that has usually been removed before we eat them. (ex. almonds, walnuts,pecans.) A peanut is also a legume, not a "nut"

10. Some of the environmental factors are : Light, Temperature, Humidity, Soil Water, Wind

11. These pores are called the stomata