In young dicot stems and stems (usually the upright, vertical portion of a plant transports substances to and the leaves) that do not increase in thickness, xylem and phloem are arranged in vascular bundles in the cortex. In older stems and all woody stems, the vascular tissues form a cylinder between the cortex and the pith. The vascular bundles in a monocot are scattered throughout the stem. In vascular plants, the dominant sporophyte has two kind of well-defined conducting tissues. Xylem is specialized to conduct water and dissolved minerals, and phloem is specialized to conduct organic nutrients and hormones.
Epithelial Tissue: Epithelial tissue covers the whole surface of the body. It is made up of cells closely packed and ranged in one or more layers. This tissue is specialised to form the covering or lining of all internal and external body surfaces. Epithelial tissue that occurs on surfaces on the interior of the body is known as endothelium. Epithelial cells are packed tightly together, with almost no intercellular spaces and only a small amount of intercellular substance.
Clearly, such delicate thin cells cannot offer much protection and their chief function is to allow materials to pass through via diffusion and osmosis. Simple squamous epithelium is found in the walls of; lung alveoli, blood capillaries and Bowman’s capsule of nephrons. As their names propose, cuboidal cells are cube-shaped, with spherical nuclei. They often line ducts and tubes and can allow materials
The shape of a cell is related to its function because of the adaptations made throughout time to make the cell as efficient as it can be. There are two types of cells, eukaryotic cells, which are generally plant and animal cells and prokaryotic cells which relate to bacteria and fungi, which undergo asexual production. Plants are anchored into the ground by roots. The function of roots is the transportation of water and mineral ions from the soil into the xylem to transport around the plant. The roots have an outer layer of cells called root hair cells that have a specific shape that makes the uptake of water and mineral ions more efficient.
The first plate had two colonies both larger spots that were across the plate from each other growing on the sides or ledges of the plate. The second dish also had either one large colony, or two smaller ones that had grown together fusing to create one large colony, on the ledge of the plate. The third plate did not have any growth. The forth plates exhibited too many colonies to count; there was a lawn of growth, a fuzzy white covering of bacteria that stretched across
Microscopic fungi absorb dissolved nutrients from their surroundings directly through their cell walls. However, nutrients typically enter larger fungi by diffusing into stringy strands of root-like hyphae growing through the substrate. The term “substrate” in this instance refers to the dead or living thing that the fungus feeds upon, such as soil or leaf litter. The strands of the hyphae absorb water and nutrients from the surroundings, giving energy to the fungus for growth and reproduction. When a fungus has a thick mat-like growth of lots of hyphae this is known as a mycelium.
It is most likely that the best and most widely used of the natural fibres is cotton. A large advantage of cotton is that it is produced in the form of almost pure fibres, packed around the seeds. Therefore, there is no need for retting or other treatment. Single cotton fibre cells are very long; however they are not long enough to
Although they are eukaryotes like plants and animals, the major difference is that fungal cells have cell walls that contain chitin, unlike the cell walls of plants, which contain cellulose. Fungi lack the chlorophyll necessary for photosynthesis and must therefore live as parasites or saprophytes Parasites: plant or animal that at some stage of its existence obtains its nourishment from another living organism called the host. Parasites may or may not harm the host, but they never benefit it. They include members of many plant and animal groups, and nearly all living things are at some time hosts to parasitic forms. Many bacteria are parasitic on external and internal body surfaces; some of these invade the inner tissues and cause disease.
Water passes from cell to cell by osmosis. They are only a few cells thick. They do not have true Roots, Leaves, or Stems. | Trypanosome | protista | sarcomastigophora | They are unicellular. they have natural hosts that evolve with them to ensure mutual survival.
Epithelial tissues line the cavities and surfaces of structures throughout the body, and also form many glands. Functions of epithelial cells include secretion, selective absorption, protection, cellular transport and detection of sensation. Epithelial layers are avascular, meaning they contain no blood vessels and rely on underlying vascular tissues to absorb nutrients from. Epithelia can also be organized into clusters of cells that function as exocrine and endocrine glands. Exocrine and endocrine epithelial cells are highly vascular.