Answer:
Cells organized into tissues
Explanation:
cells in complex multicellular organisms like people are organized into tissues, groups of similar cells that work together on a specific task
Answer:
D)Lycophyta
Explanation:
The seedless vascular plants or the pteridophyte forms one phylum of the plant kingdom. The pteridophyte kingdom can be classified into three groups: the Sphenophytes, the pteridophytes and the Lycophytes.
The Lycophyte group contains about 1000 living species as it is the most primitive group of vascular plants.
The species is characterised by the presence of the microphyll like the Selaginella and Lycopodium.
The rhizoids of the gametophyte of these plants form the mycorrhizal association with the fungi.
Thus, Option-D is the correct answer.
Answer:
The correct answers are option A. "tethering proteins to the cell cortex", B. "using barriers such as tight junctions", C. "tethering proteins to the extracellular matrix", D. "forming a covalent linkage with membrane lipids", E. "tethering proteins to the surface of another cell"
Explanation:
According to the fluid-mosaic model, the components of cell membranes are in constant movement forming a barrier to avoid unwanted exterior component internalization and to avoid the loss of precious internal components. This constant movement could cause that proteins move across the plasma membrane. But, this is avoided by several mechanisms including:
A. Tethering proteins to the cell cortex. The cell cortex is a rigid structure made of actin and actomyosin. Proteins found in the plasma membrane are tethered to this structure to restrict their movement.
B. Using barriers such as tight junctions. Tight junctions are barriers found in epithelia made of claudin and occludin proteins. These barriers are impenetrable, which avoid the movement of proteins in the cell membrane.
C. Tethering proteins to the extracellular matrix. The extracellular matrix is made of several proteins and macromolecules that provide a structural and biochemical support to cells that are nearby. Proteins could be tethered to this rigid structure as well.
D. Forming a covalent linkage with membrane lipids. The proteins in the cell membrane that form a covalent linkage with membrane lipids are known as lipid-anchored proteins, or lipid-linked proteins.
E. Tethering proteins to the surface of another cell. When cell-cell communication take place it is possible that proteins in the cell membrane got tethered to the surface of the other cell.
Answer:
Well, on one hand, this is a good thing as negative effects of the high demand for wood such as deforestation can be minimised. This will also sustain the supply of wood for several applications. However, there could be negative consequences of propagating such genetically-modified trees, which were not stated or are not yet known. For instance, the trees could be extreme soil nutrient consumers—depleting soil nutrients at a faster rate than they can be replenished and rendering such soil infertile in a short period.
Answer: As a fertilized human egg divides, it first becomes a solid ball of cells, the morula. ... The cells of the outer layer of the blastocyst eventually form part of the placenta. Inside the ball is a small clump of cells, the inner cell mass, that will form all the tissues in the body.
Explanation:
