Answer:
Random segregation of homologous chromosomes makes the two siblings differ from each other for 0-23 chromosomes.
Explanation:
Sexual reproduction adds genetic variations in the progeny by crossing over, independent segregation of homologous chromosomes and random fusion of gametes. Without crossing over, independent segregation of homologous chromosomes towards opposite poles during anaphase I of meiosis may result in two siblings to vary from each other for 0-23 chromosomes.
There is an equal probability of each of the two siblings to get a chromosome from mother or father. Hence, irrespective of the variations provided by crossing over, random segregation of homologous chromosomes makes the two siblings differ from each other for 0-23 chromosomes.
Question is incomplete. Complete question is as follows:
The ____ abuts the lumen of the alimentary canal and consists of epithelium, lamina propria, and muscularis mucosae.
Answer:
Mucosa
Explanation:
Mucosa or mucosal membrane forms the lining of many cavities in the body like the alimentary canal and also covers many internal organs. It lines reproductive, digestive and respiratory system. In the gastrointestinal tract the mucosa is made of three layers: epithelium, lamina propria and muscularis mucosae.
The epithelium of mucosa is made of simple columnar epithelium cells. It consists of many types of cells like parietal cells (secrete HCL) and foveolar cells (secrete mucus). Lamina propria is a loose connective tissue present beneath the epithelium. It provides nutrition and support to epithelium. Muscularis mucosae has smooth muscle fibers which helps the glands on the surface to secrete their contents and also increase the contact between contents of lumen and epithelium.
The following are the characteristics of Cnidaria:
1. The organisms have specialized stinging cells known as cnidocytes.
2. Two types of body plans exist, that is, polyp and medusa.
3. The phenomenon of alternation of generation is observed.
The following are the characteristics of Porifera:
1. The organisms lack symmetry.
2. The adult forms are sessile.
3. The organisms obtain food by filtering water.
Answer:
The correct answer is - Protein molecule.
Explanation:
The cell membrane is the outer membrane of the cell that differentiates the external environment from the internal components of the cell. The cell membrane is made up of two major components that are lipids and proteins.
Proteins are present as channels and in the form of membrane proteins in between the lipid bilayer. Protein is the molecule that denatured or destroyed at high temperatures such as 70 degrees.
