Answer:
The cell of amoeba is shaped differently than the classical round or boxy shape seen in textbooks.
Explanation:
Amoebas are unicellular organisms i.e consisting of a single cell. The amoebic cell can change its shape due to pseudopods. Pseudopods are structures in the amoeba that allow movement of the cell as well as help the amoeba to trap food by engulfing the particles. The species of amoeba are differentiated based on pseudopods. Amoeba also possess contractile vacuoles that helps it to get rid of the extra water.
An arid environment is characterized by hot and dry climatic conditions. Plants and animals are adapted to survive in this harsh conditions. Rainfall is minimal to intermittent.
In arid environment, the climatic weathering is very slow because of no to minimal rainfall.
Mechanical or physical weathering most common in an arid environment is THERMAL WEATHERING due to constant increase in temperature.
Answer:
Explanation:
An epitope (antigen determinants) is the part of an antigen that interacts with antibodies.
Epitopes bind to antibody molecules via T-cell receptors in a region known as complementarity determining region (CDR) and the Major histocompatibility complex (MHC) participates in this by forming complexes with peptides. The MHC helps the T-cell to recognise epitopes of antigens and discriminate self from non-self.
The MHC, T-cell works together to bring about the binding of epitopes to antibody molecules.
The main function of MHC molecules is to bind to antigens derived from pathogens and display them on the cell surface for recognition by the appropriate T-cells.
It should be noted that the amino acid sequence of the CDR determines the shape of the binding sites of the T-cell and the antibody that can be bound by an epitope.
The consequences of the interactions are;
1. MHC-peptide complex helps T-cell receptors bind to epitopes and thus antibodies
2. The shape of the binding sites (CDR) determines the antibodies that can be attacked any abnormalities at this point will affect the adaptive immune system.
Answer:
C) They should send signaling molecules across a small extracellular space.
Explanation:
To send a message to nearby cells, signal molecules only need to cross a small amount of space. Bloodstream (choice A) is used for long-distance communication, choice D is too vague, and choice B is used only for cells that are directly touching each other.
Answer:
The proportion of offspring that would be peach is 
Explanation:
Let's first put down the genotype for the F1 offspring after the pure breeding plants are crossed. From the Red fruit and Cream fruit plants, the offspring would all be RRCC. Crossing the RRCC with yyCc gives the following genotypes:
RyCC, RyCc
