BISC Final Practice Quiz! Exam

Plant hormones are chemical substances that regulate various aspects of plant growth and development. They have multiple effects on plants, influencing processes such as cell division, elongation, and differentiation. Plant hormones are active not only in developing plant embryos but also in adult plants, where they play a crucial role in controlling growth, flowering, and fruiting. Therefore, the correct answer is "all of the above" as plant hormones have multiple effects and are active in both developing plant embryos and adult plants.

Meiosis is the process of cell division that produces gametes, which are reproductive cells. In the case of an ovule, meiosis produces megaspores, which are the precursor cells for the female gametophyte. During meiosis, a single diploid cell undergoes two rounds of division, resulting in the formation of four haploid megaspores. Therefore, the correct answer is four.

The correct answer is carpel. A carpel is the female reproductive organ of a flower. It contains one or more ovaries, where eggs develop. Fertilization occurs within the carpel, and once fertilized, the ovaries mature into seeds.

Photoperiodic refers to the response of plants to the duration of light and darkness in a day. Some plants require specific day lengths to initiate flowering. This response is controlled by the plant's internal biological clock and is influenced by the changing seasons. Therefore, the correct answer is photoperiodic.

Seeds are mature ovules, and fruits are mature ovaries. Ovules are the structures within the ovary that contain the female reproductive cells, which develop into seeds after fertilization. Ovaries, on the other hand, are the female reproductive organs that contain the ovules and mature into fruits after fertilization. Therefore, the correct answer is "ovules; ovaries."

When a new plant forms from a stem that broke off of the parent plant, it is an example of vegetative reproduction. In this process, a new plant is produced from a vegetative part of the parent plant, such as a stem or a leaf, without the involvement of seeds or spores. This allows the parent plant to produce genetically identical offspring, maintaining the characteristics of the parent plant. Vegetative reproduction is commonly observed in plants like succulents, strawberries, and potatoes.

Cotyledons are the embryonic leaves of a plant, which are present in the seed and serve as the primary source of nutrients for the developing embryo. They are part of the embryo sporophyte, which is the diploid phase in the plant life cycle that produces spores through meiosis. Carpels are the female reproductive organs of a flower, accessory fruits are fruits formed from tissues other than the ovary, and petioles are the stalks that attach leaves to the stem. Therefore, the correct answer is embryo sporophytes.

Phytochromes are the photoreceptors in plants that are responsible for sensing and responding to light. They play a crucial role in regulating various processes such as seed germination, flowering, and photoperiodism. When sunlight hits the phytochromes, it triggers a series of chemical reactions that activate or deactivate certain genes, ultimately resetting the biological clocks in plants. Therefore, phytochromes are the correct answer as they are directly involved in the process of resetting biological clocks in plants.

Blue light is the stimulus for phototropism because it is the specific wavelength of light that plants perceive and respond to. Phototropism is the growth or movement of a plant in response to light, and blue light is known to be the most effective in triggering this response. When plants detect blue light, it activates photoreceptor proteins called phototropins, which then initiate the growth and bending of plant stems and leaves towards the light source. Therefore, blue light plays a crucial role in regulating phototropism in plants.

Solar tracking is similar to phototropism because both involve the movement or orientation of an organism or structure in response to light. Phototropism is the growth or movement of a plant towards or away from a light source, while solar tracking refers to the movement of solar panels or other devices to optimize their exposure to sunlight. In both cases, the organisms or structures are responding to the direction or intensity of light in order to maximize their energy capture.

Meiosis is a type of cell division that results in the formation of haploid cells, which have half the number of chromosomes as the parent cell. In the case of pollen sacs, meiosis produces microspores, which are haploid cells that develop into male gametophytes. These microspores eventually give rise to the stamens, the male reproductive structures of flowering plants. Therefore, the correct answer is microspores.

The seed coat forms from the integuments. Integuments are protective layers that surround the ovule and develop into the seed coat after fertilization. They provide protection to the developing embryo and help in seed dispersal.