Notes of Biology

Asexual Propagation is the process of using plant materials such as the stems, leaves, and roots to multiply the number of plants. These plants eventually grow to be a brand new plant that is genetically identical to the parent plant it came from. In several types of plants, asexual propagation is the fastest means of new plant growth. Asexual propagation is also a good way to maintain a plant species because they are genetically identical. In this process, adventitious roots are seen in the growing cycle. Adventitious roots are those that grow form parts of the plant that they normally would not grow from. The cuttings must do

For example, the Sea Monkey females don’t breed with males, making the males go and breed with other species, creating hybrids. Also, it gave an example, involving both asexual and sexual reproductive shrimp. The results of that were only that half of the sexual population can produce eggs, while every individual in the asexual one can. This basically means that it won’t be too soon before the asexual population dominates over the other. This article related to current unit topics because right now we are talking about cell reproduction and something that is involved in that is Mitosis. In the article it mentioned how more DNA is needed to be built with double the amount of chromosomes from the asexual reproduction. Currently, we are learning about how in order for the cells to split, they need to copy the DNA to the chromosomes. Well, with double the amount of chromosomes, copying all that DNA to each is a very difficult task. Another example is with chromosomes, now with sexual reproduction a set of chromosomes is needed from both the mother and father, but in the case of asexual reproduction and the Sea Monkeys, the females just combine two of the eggs, making it have enough chromosomes to

21) As sperm are produced, they go through several stages. Which stage develops directly into mature motile sperm?

Hypophosphatemia (vitamin D-resistant rickets) is inherited as an sex-linked dominant trait. The relevant gene is found on the X chromosome

_____ In swine, when a pure-breeding red is crossed with a pure-breeding white the F1 are all red. However, the F2 shows 9 red, 1 white and 6 of a new color, sandy. The Sandy phenotype is most likely determined by

D) Sexual reproduction is more likely to increase genetic variation than is asexual reproduction. E) Only asexual

There are many methods of reproduction, but the two main methods are sexual and asexual, but which one is more efficient or beneficial. Sexual reproduction is the fusing of two gametes to produce an offspring. This form of reproduction is used by a lot of organisms, including us. Asexual reproduction is reproduction that only involves one parent. (“Pros and cons of sexual and asexual reproduction”). I am going to focus on asexual reproduction and the Desert Grassland Whiptail Lizard. This unique lizard uses asexual reproduction. Asexual reproduction is better for this species of lizards because it only requires one parent, it is less risky, and the population is only female.

“If no such variations exist, the population rapidly goes extinct because it cannot adapt to a changing environment” (O’Neil, 1998-2013). Scientists call this reproductive success. “Within a specific environment context, one genotype will be better than another genotype in survival or reproduction for certain reasons having to do with the way its particular features relate to the environment or relate to other organisms within the population” (Futuyma, 2000-2014). The theory of evolution is explicable through various kinds of scientific research.

II. There is a risk of extinction since the same weaknesses are passed on, unlike in sexual reproduction where there are genetic variations. III. Asexually reproduced organisms are less able to adapt to different environments as compared to sexually reproduced organisms. 6) Compare and contrast monogamy, polygyny, polyandry, and promiscuity.

In contrast, when two individuals mate, the cells go through cell division or meiosis. This allows four daughter cells to produce from the original first cell. Since the offspring has genes and traits from both parents, the offspring will be unique. This is advantageous for evolutionary changes. Since each offspring is unique in their genetic material, some won’t be affected by a disease, such as HIV, AIDS, and viruses, as others might. This allows these offspring to survive. The

In most cases sexual difference are with in species may intersexual or intrasexual, but according to Darwin there are other ways sexual difference can occur in a species. Within the species sexual difference can based on the genetics and the their genotypes. The species sexual difference can be based on what traits are being expressed. Take for instance the sex chromosomes where males posses the XY chromosome and females posses the ZY chromosome. When evaluating the chromosome in mammals, males have a penis to ejaculate sperm and females have mammary glands to produce milk for the young.

Do you know how you were born? Do you know how you came to be? The reproductive system is the system that made that all possible. Without the reproductive system you wouldn’t have been born. In order to produce offspring, the male and female reproductive systems have to be different. Each system has different parts, problems and care. Each system have different purposes, the male reproductive system’s function is to produce sperm, while the female reproductive system’s function is to produce ova, store ova and house a fertilized egg.

Offspring differ somewhat from their parents and from one another. Instructions for development are passed from parents to offspring in thousands of discrete genes, each of which is now known to be a segment of a molecule of DNA. This essay will explore some of the reasons behind how and why these differences in appearance arise, from the base sequence of DNA through to the observed phenotype.

Each parent contains two factors, which may or may not be the same (homozygous or heterozygous)

Records show that the practice of grafting is an ancient one, dating back well before the time of Christ It was once believed that any plant could be grafted on any other. This probably arose from observations made in tropical areas where seeds sometimes lodged in the cleft of a tree where seeds germinated and grew in the organic matter that had accumulated there. However, today, we know that only very closely related plants are capable of being grafted. Many forms of grafting are practiced, and the technique known as budding is widely used in the production of fruit trees, roses, and ornamental trees and shrubs. Without the practice of grafting many of the popular varieties we know today, such as the Delicious Apple or the Peace Rose, could not have been maintained. Wrong was the man who wrote in 1889: We doubt if there is a greater nuisance in the whole practice of gardening than the art of grafting. It is very clever, it is very interesting, but it will be no great loss if it is abolished altogether. While the technique of budding generally works best during June, July and August, many other forms of grafting are done just before plants begin new growth and are still dormant. Three terms are important in any discussion of grafting: stock, scion, and cambium. The stock is the rooted lower portion of a plant on which the graft is to be made. The scion is the shoot, bud or piece of twig to be fastened on the stock. Most important of all is the cambium, a thin layer of pale