After double fertilization, a zygote and ________ form.an ovule endosperm a cotyledon a suspensor
Double fertilization in angiosperms is a process that ensures both the formation of the embryo, giving rise to a new plant, and the endosperm, a nourishing tissue. Double fertilization is a process in which one gamete joins the oosphere, while another joins the polar nuclei. For this phenomenon to occur, a number of factors are required, which begin with pollination.
The result of double fertilization occurs when the male gamete merges with the female gamete called the oosphere, this fusion is responsible for giving rise to the diploid embryo, which can form a new individual. Already the gamete that fuses to the polar nuclei is responsible for giving rise to the so-called endosperm, which is triploid. In short, after double fertilization a zygote and an endosperm form.
Fungi, like the one that causes athlete's foot, are considered A. saprobic B. chemoautotrophic C. heterotrophic D. photoautrotrophic
Fungi, like the one that causes athlete's foot, are considered
Which of the following can be a stimulus for contraction in all three muscle tissue types? A) epinephrine B) thyroid hormone C) testosterone D) parathyroid hormone E) acetylcholine
The correct answer will be option-E.
Acetylcholine belongs to a group of chemical messengers which also acts as neurotransmitters in the synaptic transmission of the signals.
The acetylcholine is present in the vesicles in the synaptic knob which when released at the neuromuscular junction cause the contraction of the skeletal muscle along with cardiac and smooth muscle.
The mechanism of action is different in different muscles as the neurotransmitter binds to the nicotinic receptors present on the motor endplate and opens ligand-gated sodium channels.
In smooth and cardiac muscle it binds to the muscarinic receptors and cause the release of calcium ions and potassium ions respectively and cause muscle contraction.
Thus, option-E is the correct answer.
Urban areas use __________ energy __________ than rural areas, mostly because so many more people live there. A) solar power B) more; in total C) less; in total D) an electric furnace
The correct answer is - B) more; in total.
The urban areas use much more energy than the rural areas, by far. The reasons for that are numerous, with the two biggest being the number of people and the industry.
The number of people living in urban areas is higher than the number of people living in rural areas. Also, the people in the urban areas use much more energy because they rely on much more technology, technology that uses energy in order to work.
Most of the industry is also located in and around the urban places. The industry is a huge consumer of energy, thus increasing the usage of energy further more.
Why is a cap added to mRNA, but not to tRNA or rRNA?A-Transfer RNA and rRNA exhibit complex structures with double stranded regions. The three-dimensional shapes of these molecules keep the 5\' end of the RNA away from the enzymes that process the cap.B-Transcription and processing of mRNA occur in the nucleus, where cap binding proteins are found. These proteins, which add and modify the cap, are not found in the cytoplasm, where tRNA and rRNA are transcribed and processed.C-Each of the three types of RNA are transcribed by different RNA polymerases. Only RNA polymerase II, involved in mRNA synthesis, contains a domain capable of interacting with enzymes that form the cap.D-Only mRNA contains introns. Capping occurs simultaneously with intron removal because the same enzymes and proteins involved in both of these processes must bind to RNA at the same time.
The correct option is C ' Each of the three types of RNA are transcribed by different RNA polymerases. Only RNA polymerase II, involved in mRNA synthesis, contains a domain capable of interacting with enzymes that form the cap.'
All the different type of RNA's undergo the process of transcription. However, their transcription is carried on by different types of RNA polymerases.
The transcription of the mRNA is carried by RNA polymerase II. The process of capping is essential so that the mRNA is stopped from degradation.
The rRNA is transcribed by RNA polymerase I which cannot add a cap tothe RNA.
The tRNA is transcribed by the RNA polymerase II, but the domain is different which cannot undergo the process of capping.
Why is it necessary for each gemete to contain only half as many chromosomes as a body cell
This is for the offspring to show traits that come from both the mother and father.
Gametes are formed by a kind of cell division called meiosis in which the chromosome number is halved. Thus the said gamete cell is said to contain a haploid number of chromosomes.
The fusion of two haploid gametes is called fertilization. It results in the formation of single celled zygote which has a diploid number of chromosomes. The zygote now divides and develops to produce the offsprings whose somatic cells are diploid.
WILL BE MARKED BRAINLIEST AND PLUS 12 POINTS Which detail from the passage best explain why plants photosynthesize?