As for true tissue, arguments are carried out by different parties and scientists where some do agree that sponges have true tissues that specialized to perform particular function and some are not. As the basic criteria itself failed to classify the sponges into advanced phyla, other characteristics shown by advance organisms are totally been neglected off Porifera. Sponges’ bodies are fully designed with ample of tiny pores that make them efficient filter feeders. The filter feeding system is really fundamental for the organisms under this phylum as they possess an inactive lifestyle by being sessile during adult stage. They fully dependent on the water current created by continuously beating flagellated choanocytes that decorating the internal wall of their body.
This kind of experiment has been conducted long time ago by some scientists such as Aristoteles, Herophilus, and Erasistratus which performed the experiments to discover the functions of living organisms and is used until now. Chimpanzees, mice, dogs, and fish are some animals which is frequently used in the experiment. Many of this experiments (which was conducted
Abstract: Drosophila Melanogaster are fruit flies. Previous research has shown that fruit flies are the most logical organism to use to study genetics. This is most likely because they reproduce and regenerate quickly and they are easy and relatively cheap to handle. In our experiment, we observed flies (F2) with unknown phenotypes that we had to discover. After discovering the phenotypes that we were looking for, we tried to figure out the parents (F2), which was the purpose of the experiment.
Evolution can be seen in the anatomy of animals today. Completely distinct species share alike features. For example, humans and birds have the exact same bones in the forearm area. This shows that two different species came from a common ancestor. It is highly unlikely that each species evolved this way independently.
Nada ElMoussa 17701179 -Title: Examination of plant and animal cells under the microscope. -Aim: To investigate plant and animal cells using light microscopy. -Introduction: A plant cell is the structural and functional basic unit of life in kingdom plantae. Plant cells are eukaryotic cells, where their DNA is housed within a nucleus, as well as other specialized structures called organelles including: the cell wall, central vacuole, chloroplasts, cell membrane, cytoplasm, mitochondria, Golgi apparatus, and endoplasmic reticulum (1). Fig (1): A plant cell under the microscope (2).
In the conjunctival epithelium, the superficial squamous epithelial cells are usually CK4 positive, while the glandular goblet cells are CK7 positive (Table 1). CKs consist of pairs of type I (acidic) and type 2 (neutral or basic) CK (Rao, et al., 2014). In response to stress (dryness, shear stress) non-keratinized epithelium can react by keratinizing to form a granular layer and stratum corneum to protect the tissue. This change can be seen in the ocular surface in DED patients (Maumenee, 1979) and in the OME (linea alba) (Canaan & Meehan, 2005; Nanci, 2013)A mucin layer covers and protects the wet epithelial surfaces, such as the ocular surface and the lumen of the gastrointestinal tract, the lungs, and the oral cavity (Argueso & Gipson, 2001; Frenkel & Ribbeck, 2015; Linden, et al., 2008). Mucins are large, highly glycosylated glycoproteins that are either secreted or membrane-bound.
Both animal and plant cells have some similar organelles such as, the plasma membrane, nucleus, mitochondria, endoplasmic reticulum, ribosomes and Golgi apparatus. Although they have a wide variety of similarities, they also have their differences. Plant cells have a rigid structure that surround the cell membrane called the cell wall, while animal cells do not; the cell wall helps retain the shape of the plant cell.
Assignment unit 3 1. Unlike prokaryotic cells, eukaryotic cells have: 1) a membrane-bound nucleus; 2) numerous membrane-bound organelles such as the endoplasmic reticulum, Golgi apparatus, chloroplasts, mitochondria, and others; and 3) several, rod-shaped chromosomes. Because a eukaryotic cell’s nucleus is surrounded by a membrane, it is often said to have a “true nucleus.” The word “organelle” means “little organ,” and, as already mentioned, organelles have specialized cellular functions, just as the organs of your body have specialized functions. At this point, it should be clear to you that eukaryotic cells have a more complex structure than prokaryotic cells. Organelles allow different functions to be compartmentalized in different areas