1.
Describe examples of how a mutation can be harmful, beneficial or neutral.
2.
A ____ mutation is more drastic because it affects many genes.
Correct Answer
A. Chromosomal
Explanation
A chromosomal mutation is more drastic because it involves changes in the structure or number of chromosomes, which can have a significant impact on the expression of multiple genes. This type of mutation can lead to the deletion, duplication, inversion, or translocation of large segments of DNA, affecting the functioning of multiple genes at once. In contrast, point mutations involve changes in a single nucleotide base pair and typically affect only one gene or a small portion of it. Therefore, chromosomal mutations have a broader and more profound effect on the genetic makeup of an organism.
3.
Which of the following is not an example of asexual reproduction?
Correct Answer
A. Regeneration
Explanation
Regeneration is the process by which an organism regrows a lost or damaged body part. This is a form of asexual reproduction as it involves the production of a new individual from a single parent without the involvement of gametes. Therefore, the correct answer is Regeneration, as it is an example of asexual reproduction.
4.
The specialized sex cells in a plant are the -
Correct Answer
A. Pollen and ovum
Explanation
The specialized sex cells in a plant are pollen and ovum. Pollen is the male sex cell, produced by the stamen, and is responsible for fertilizing the ovum, which is the female sex cell, produced by the ovary. This fertilization process leads to the formation of seeds and subsequent reproduction in plants.
5.
Which is the first step of mitosis?
Correct Answer
A. InterpHase
Explanation
Interphase is the first step of mitosis. It is the longest phase of the cell cycle and involves the cell preparing for division by growing and replicating its DNA. During interphase, the cell also carries out its normal functions and prepares for the subsequent stages of mitosis. Anaphase, cytokinesis, and prophase are all stages that occur after interphase in the process of mitosis.
6.
The pictured hydra reproduces ____ through ____.
Correct Answer
A. Asexually, budding
Explanation
The hydra in the picture reproduces asexually through budding. Asexual reproduction involves the production of offspring without the involvement of gametes or the fusion of genetic material from two parents. In budding, a small bud grows out from the parent organism and eventually detaches to become a new individual. This process allows for rapid reproduction and population growth in hydra.
7.
During __ the chromatids are pulled apart by the spindle fibers.
Correct Answer
A. AnapHase
Explanation
During anaphase, the chromatids are pulled apart by the spindle fibers. This is the stage of mitosis where the sister chromatids, which were previously attached at the centromere, separate and move towards opposite poles of the cell. The spindle fibers exert force on the centromeres, causing the chromatids to be pulled apart and ensuring that each daughter cell receives a complete set of chromosomes.
8.
“Crossing over” occurs during ____.
Correct Answer
A. PropHase II
Explanation
Crossing over occurs during Prophase I of meiosis, not Prophase II. In Prophase I, homologous chromosomes pair up and exchange genetic material through a process called crossing over. This genetic exchange leads to genetic variation among offspring. Prophase II is the stage where the spindle fibers form and the nuclear envelope breaks down, preparing the cell for the second division of meiosis.
9.
A sudden genetic change (change in base pair sequence of DNA) is a ___.
Correct Answer
A. Mutation
Explanation
A sudden genetic change, also known as a mutation, refers to a change in the base pair sequence of DNA. This change can occur spontaneously or be induced by external factors such as radiation or chemicals. Mutations can lead to a variety of outcomes, including genetic disorders, changes in physical traits, or even beneficial adaptations. Therefore, in the context of the given options, the correct answer is "Mutation."
10.
Expectant mothers can get a test for genetic mutations called a ____.
Correct Answer
A. Karyotype
Explanation
Expectant mothers can get a test for genetic mutations called a Karyotype. A karyotype is a test that examines the number and structure of an individual's chromosomes. It can help identify genetic abnormalities or mutations that may be present in the fetus. This test is commonly performed during pregnancy to assess the risk of certain genetic disorders and to provide information for prenatal diagnosis and counseling. A karyotype can provide valuable information about the health of the fetus and help guide medical decisions for the expectant mother.
11.
The process by which a single organism produces genetically identical offspring is called -
Correct Answer
A. Sexual reproduction
Explanation
Sexual reproduction is the correct answer because it involves the fusion of gametes from two parents to produce genetically unique offspring. This process allows for genetic variation and diversity in the population. Mitosis is a type of cell division that produces genetically identical cells, but it does not involve the production of offspring. Meiosis is a type of cell division that produces gametes, but it does not result in genetically identical offspring. Asexual reproduction involves the production of offspring without the involvement of gametes or genetic recombination, resulting in genetically identical offspring.
12.
Specialized sex cells are called ………………………………
Correct Answer
gametes
Explanation
Gametes are specialized sex cells that are involved in sexual reproduction. They are responsible for transmitting genetic information from one generation to the next. In males, gametes are called sperm, while in females, they are called eggs or ova. Gametes are produced through a process called gametogenesis, which involves meiosis. During fertilization, a sperm and an egg fuse together to form a zygote, which eventually develops into a new individual. Gametes have half the number of chromosomes compared to other cells in the body, allowing for the combination of genetic material from two parents.
13.
Male animals have .......................................
Correct Answer
Sperm
Explanation
Male animals have sperm, which is the reproductive cell necessary for fertilization. Sperm is produced in the testes and is responsible for carrying the male genetic material to the female reproductive system. It is a specialized cell with a long tail that enables it to swim towards the egg for fertilization. Sperm is essential for sexual reproduction in most animals and plays a crucial role in the continuation of the species.
14.
Female animals have .........................................
Correct Answer
Ovum
Explanation
Female animals have ovum, which is the reproductive cell or egg produced by the ovaries. Ovum is necessary for sexual reproduction as it can be fertilized by a sperm cell to form a zygote, which eventually develops into an embryo. Ovum is typically larger in size compared to sperm cells and contains all the genetic material required for the development of a new organism.
15.
After Telophase I there are ____ daughter cells that each have _________ Chromosomes (human)
Correct Answer
2, same number
Explanation
After Telophase I of meiosis, there are two daughter cells that each have the same number of chromosomes as the parent cell. This is because during Telophase I, the homologous chromosomes separate and move to opposite poles of the cell, resulting in two daughter cells that each have half the number of chromosomes as the parent cell. However, each chromosome is still composed of two sister chromatids, so the total number of DNA molecules remains the same in each daughter cell.
16.
After Telophase II there are ____ daughter cells that each have _______________chromosomes (human)
Correct Answer
4, half number
Explanation
After Telophase II of meiosis, there are four daughter cells that each have half the number of chromosomes as the parent cell. In humans, the parent cell has 46 chromosomes, so each daughter cell will have 23 chromosomes. This is because during meiosis, the parent cell undergoes two rounds of cell division, resulting in the formation of four haploid daughter cells with half the number of chromosomes as the parent cell.
17.
The Planaria pictured are reproducing through a type of asexual reproduction called
Correct Answer
Regeneration
Explanation
The Planaria pictured are reproducing through a type of asexual reproduction called regeneration. Regeneration is the ability of an organism to regrow or replace lost or damaged body parts. Planaria are known for their remarkable regenerative abilities, as they can regenerate their entire body from just a small piece. This process involves the growth and differentiation of cells to form new tissues and organs. Through regeneration, Planaria can create genetically identical offspring without the need for sexual reproduction.
18.
All mutations cause life-threatening diseases.
Correct Answer
B. False
Explanation
The statement "All mutations cause life-threatening diseases" is not true. Mutations can have a range of effects, from being neutral or having no impact on an organism's health to causing mild or severe diseases. Some mutations may even be beneficial or provide an advantage in certain circumstances. Therefore, it is incorrect to say that all mutations cause life-threatening diseases.
19.
Interphase is the first stage of mitosis.
Correct Answer
A. True
Explanation
Interphase is indeed the first stage of mitosis. It is the period between cell divisions where the cell prepares for division by growing, replicating its DNA, and carrying out normal cellular functions. During interphase, the cell undergoes three subphases: G1 (gap 1), S (synthesis), and G2 (gap 2). In G1, the cell grows and carries out its normal functions. In S phase, DNA replication occurs, resulting in the formation of sister chromatids. In G2, the cell continues to grow and prepares for cell division. Only after interphase is complete does the cell proceed to the actual stages of mitosis.
20.
Mitosis results in two identical daughter cells.
Correct Answer
A. True
Explanation
During mitosis, a cell undergoes a process of division where the genetic material is replicated and distributed equally between two daughter cells. This results in the formation of two identical daughter cells, each containing the same number and type of chromosomes as the parent cell. Therefore, the statement "Mitosis results in two identical daughter cells" is true.
21.
In the process of meiosis the parent cells are genetically different from the daughter cells.
Correct Answer
A. True
Explanation
During meiosis, the parent cells undergo a process of genetic recombination known as crossing over. This results in the exchange of genetic material between homologous chromosomes, leading to genetic diversity in the daughter cells. As a result, the daughter cells produced through meiosis are genetically different from the parent cells. Therefore, the statement "In the process of meiosis the parent cells are genetically different from the daughter cells" is true.