Answer:
Ligand-receptor interaction is the first interaction that triggers cell signalling.
Ligands are the hormones, drugs or neurotransmitters that specifically bind with receptors present in cell surface to initiate cell signalling. Ligand binding to the receptor is reversible. Binding of the ligand to the receptor can activate or inactivate receptor. Activation may lead to cell signalling pathways. Inside cells, there are secondary molecules which on activation starts a cascade of reactions. which in-turn regulate the function of the ligand molecule.
At first, the activated receptor relates with G proteins molecules in the cell.
before the ultimate physiological effect of the ligand on the cell's behavior is produced Therefore, the cellular signaling starts as soon as the first messenger (the ligand) binds to its receptor.
hope this helps
Answer:
A limiting factor is anything that constrains a population's size and slows or stops it from growing. Some examples of limiting factors are biotic, like food, mates, and competition with other organisms for resources.
<span>The answer is shared an evolutionary
history. Homologous structures evolved
from the same ancestor structure. An example of homologous features is the four
limbs of all tetrapods. In birds, the forelimbs evolved
into wings while in crocodiles they still used for walking, and in humans, they evolved into hands. </span>
Answer:
photosynthesis
green algae
haploid
sporophyte
xylem
d
a
c
b
Early land plants like mosses did not have vascular tissue. They must absorb their water directly from their surroundings, such as growing on rocks or trees that are moist. You find mosses in damp areas for this reason. They cannot grow in drier climates because they cannot pull water from the ground like vascular plants. Ferns are also suited to reproduce in more moist/humid climates because water must be present for their gametes (sperm and eggs) to find one another for fertilization. Seeds are adaptations by angiosperms and gymnosperms that allow for waterless fertilization. Either wind or animal pollinators help spread pollen and help the sperm reach egg cells for fertilization to occur. For that reason, these plants are better suited to survive in drier, modern climates.
Explanation:
PF make brainliest plz
Answer:
<h3>The micro-organisms which convert the dead plants and animals to humus are known as decomposers.</h3>
<h3> Examples: Fungi and Bacteria. Decomposers recycle and convert the dead matter into humus which mixes with forest soil and provides necessary nutrients to plants.</h3>