Answer the following question given this paragraph: Microfilaments , shown as (b) in Figure below , are made of two thin actin chains that are twisted around one another. Microfilaments are mostly concentrated just beneath the cell membrane, where they support the cell and help the cell keep its shape. Microfilaments form cytoplasmatic extentions, such as pseudopodia and microvilli , which allow certain cells to move. The actin of the microfilaments interacts with the protein myosin to cause contraction in muscle cells. Microfilaments are found in almost every cell, and are numerous in muscle cells and in cells that move by changing shape, such as phagocytes (white blood cells that search the body for bacteria and other invaders). Q: Microfilaments are mostly concentrated just beneath what? Choices: - the nucleus - the cell wall - the cytoplasm - the cell membrane A:
the cell membrane
(Question)
Answer the following question given this paragraph: CRITICAL THINKING QUESTIONS 19. How are neurons similar to other cells? How are they unique? 20. Multiple sclerosis causes demyelination of axons in the brain and spinal cord. Why is this problematic?. Q: The existence of (virtual) photons is possible only by virtue of the heisenberg uncertainty principle and can travel an unlimited distance, so the range ofthe electromagnetic for is what? Choices: - finite - simple - generated - infinite A:
(Answer)
infinite
Ques: Answer the following question given this paragraph: Copying and passing on genes (genetics) In which we consider the dynamics of genes and gene expression, and how genome dynamics leads to families of genes and facilitates evolutionary change. We consider how DNA is organized within a cell and how its organization influences gene expression. Finally we consider the behavior of regulatory networks at the molecular level and the role of molecular level noise in producing interesting behaviors. At this point we have introduced genes, DNA, and proteins, but we have left unresolved a number of important questions. These include how genomes are organized, how they evolve, how new genes and alleles are generated, and how they work together to produce the various behaviors that organisms display.327 We will touch on such trendy topics such as epigenetics (which is probably less interesting than most suppose) and the rather complex molecular and cellular level processes behind even the simplest biological behaviors. The details, where knownand often they are notare beyond the scope of this course, but the basic themes are relatively straightforward, although it does takes some practice to master this type of thinking. The key is to keep calm and analyze on! Genomes and their organization Genomes are characterized by two complementary metrics, the number of base pairs of DNA and the number of genes present within this DNA. The number of base pairs is easier to measure, we can count them. This can, however, lead to a mistaken conclusion, namely that the number of base pairs of DNA within the genome of a particular species, organism, or even tissue within an organism is fixed and constant. In fact genomes are dynamic, something that we will return to shortly. The genome of an organism (and generally the cells of which it is composed) consists of one or more DNA molecules. When we talk about genome size we are talking about the total number of base pairs present in all of these DNA molecules added together. The organism with one of the largest known genomes is the plant... Q: The genome of an organism consists of one or more what? Choices: - hemoglobin molecules - require molecules - rna molecules - dna molecules A:
Ans: dna molecules
(Q).
Answer the following question given this paragraph: Q: Poetically speaking, nature reserves are islands of what, in a sea of habitat degraded by human activity? Choices: - refuge - habitats - ecosystem - biodiversity A:
(A).
biodiversity
Ques:Answer the following question given this paragraph: Vertebrates evolved from primitive chordates. This occurred about 550 million years ago. The earliest vertebrates may have been jawless fish, like the hagfish in Figure below . Vertebrates evolved a backbone to replace the notochord after the embryo stage. They also evolved a cranium , or bony skull, to enclose and protect the brain. Q: Vertebrates evolved from primitive forms of which creature? Choices: - arthropods - humanoids - cephalopods - chordates A:

Ans:chordates
Ques: Answer the following question given this paragraph: Cysts may develop in the ovaries. A cyst is a sac filled with fluid or other material. Ovarian cysts are usually harmless and often disappear on their own. However, some cysts may be painful and require surgery. Q: What is a sac filled with fluid or other material? Choices: - a lesion - Golgi apparatus - a receptacle - a cyst A:
Ans:
a cyst