a virus will enter a host's body and the host will identify it as foreign and so, through a process probably too specific for what you need, t-cells become activated to defend against the foreign virus cells (At first, the body is able to defend against them, and sometimes completely eliminates them, but other times, the virus replicates far too fast for the immune response to handle so as it is trying to kill off the virus, the "stronger" pieces of the virus (like the survivors of the immune system attack) continue to hijack cells' equipment to replicate more of the stronger virus cells. These cells often develop a mechanism in which the body doesn't recognize as foreign, and so does not defend against it. By the time the body recognizes the cells, it is too late and the cells have replicated to a number far too large for the body to defend against d. Thus the evolution as the virus is first eliminated, but develops ways in its replicas to become unidentifiable to the body or resistant to the body's defense and therefore harder eliminate. The viral lineages that tend to survive are those that can replicate quickly and appear "normal" to the body, exchange genes with similar strains (to form basically a new virus), viruses that have an unknown reservoir (place they hide between pandemics) and those who's genes cannot be identified and therefore, vaccines/ drugs cannot be produced to defend against or stop the
STEPS OF CLONING 1. Isolation of the Donor Nucleus The nucleus of an animal cell contains the genetic material that serves as the blueprint for that animal. In the first step of cloning, scientists puncture the cell membrane with a tiny needle and syringe and use suction to extract the cell nucleus through the needle. 2. Harvest of Egg Cells For mammals, which are the animals that scientists most commonly clone, egg cells are microscopic.
Comparison chart | Meiosis | Mitosis | Definition: | A type of cellular reproduction in which the number of chromosomes are reduced by half through the separation of homologous chromosomes in a diploid cell. | A process of asexual reproductionin which the cell divides in two producing a replica, with an equal number of chromosomes in haploid cell | Function: | sexual reproduction | Cellular Reproduction & general growth and repair of the body | Type ofReproduction: | Sexual | Asexual | Occurs in: | Humans, animals, plants, fungi | all organisms | Genetically: | different | identical | Crossing Over: | Yes, mixing of chromosomes can occur. | No, crossing over cannot occur.
7. The figure to the right shows that injection of M-phase cytoplasm into an oocyte triggers the cell to enter mitosis. What would be the expected effect on cell division if cytoplasm from a G2-phase cell were injected into an M-phase cell? A. DNA replication would begin again. B. activation of all cyclin-CDK complex in the cell.
Difference between Normal and Cancerous Cells Dominique Clay Strayer University SCI 115 Mrs. Tamara Allen Difference between Normal and Cancerous Cells Based on your data and observations, what are some of the Differences between normal cells and cancer cells? A cell starts out in the stage Interphase where the cell is at rest. Next the cell if it needs to reproduce it goes through Prophase; which is the first stage of mitosis where the cell’s nucleolus and nucleus fade away and the chromatin forms chromosome spindles that appear between the centrioles that have now gone to the opposite poles of the cell. Next comes Metaphase where the sister chromosomes line up in the middle of the cells attaching to the spindles by their centromere. Then the sister chromosomes divide at the centromere retreating to opposite sides of the cell, this is called Anaphase.
Honors Biology Chapter 4 Study Guide 1. Describe the structure of the organelles described in chapter 4. ex)nucleus has a double membrane and nuclear pores. very basic 2. If a cell has an extensive Golgi apparatus what function/process would you expect that cell to do? stores proteins and alot of exporting (sending stuff out of the cell) 3.
DNA Structure and Replication True/False Indicate whether the sentence or statement is true or false. ____ 1. Even though they contain weakened or killed infectious organisms, vaccines can still cause an immune response when injected into an organism. ____ 2. Even though Avery’s experiments clearly indicated that genetic material is composed of DNA, most scientists at that time continued to suspect that proteins were the genetic material.
Bio Chapters 7-10 Vocab Chapter 7 DNA Structure and Gene Function DNA- a molecule with remarkable functions; it stores the information that each cell needs to produce protein Nucleotides-four bases of protein. Adenine (A), thymine (T), guanine (G), cytosine(C) Complementary- In DNA and RNA, the precise pairing of purines (A and G) to pyrimidine’s ( C,T, and U) Genome- is all of the genetic material in its cell Chromosome- long DNA molecules that associate closely with proteins Gene- is sequence of DNA nucleotides that codes for specific protein or RNA molecule Transcription- a cell copies a genes DNA sequence to a commentary RNA molecule Translation- the information in RNA is used to manufacture a protein by joining a specific sequence
Mitosis is the step during which the cell’s nucleus divides into two new nuclei. During mitosis, one copy of the DNA is distributed into each of the two daughter cells. Scientists divide mitosis into four parts (phases): prophase, metaphase, anaphase, and telophase. During prophase, the thread-like chromatin in the nucleus condenses to form double-rod structures called chromosomes. During metaphase, the chromosomes line up across the center of the cell.
Defining viruses is truly a challenge to scientists, who constantly debate on whether or not they should be classified as living. To be called "living" the organism must qualify under the seven categories; they must have order, be able to reproduce, be able to grow and develop, utilize energy, respond to their environment, maintain homeostasis, and adapt through evolution. Viruses qualify under all of these categories except metabolism and reproduction, for which they act as a parasite and use a host cell to do it for them. Viruses are the boundaries between biology and biochemistry, and may eventually lead to finding an ancient genome pool. Many nonliving things are needed to make a living organism.