Answer:
Carbohydrates, particularly glycoproteins act as ligands for cell surface receptors.
Explanation:
Glycoproteins
- Glyproteins are conjugate molecules comprising of carbohydrates conjugated with proteins.
- Glycoproteins play a vital role in cell-cell recognition, pathogen recognition and and cell adhesion.
- Glycoproteins on the surface of pathogens act as prominent antigens for the immune system.
Glycoproteins in Fertilization:
Several glycoproteins are attached to the surface of the zona pellucida, the envelope of the oocyte. In humans, these have been termed as ZP1-4.
Glycoprotein-sperm interaction is one of the most crucial steps in fertilization. This receptor-ligand interaction ensures the entry of the sperm into the zona pellucida, the extracellular coat, covered in glycoproteins that surrounds the oocyte or egg.
Carbohydrate binding proteins present on the surface of the sperm recognize the glycoproteins on the zona pellucida (ZP). This enables them to adhere to the surface of the ZP and also to gain access to the oocyte.
RNA has Uracil as base with Adenine but DNA has Thymine at place of that...
correct AnswerAnswer:
D- D and A
Explanation:
REAL EXPLANATION
<h3><em>Chloroplasts take energy from the sun ad make it into food by a process called photosynthesis.... it then makes the energy to power the plant..... </em></h3><h3><em>Mitochondrions are called the power house of the cell, powering and letting the cell do its work transporting more energy into the plant....</em></h3>
Soil erosion is defined as the wearing away of topsoil. Topsoil is the top layer of soil and is the most fertile because it contains the most organic, nutrient-rich materials. Therefore, this is the layer that farmers want to protect for growing their crops and ranchers want to protect for growing grasses for their cattle to graze on.
Answer: b. one atom transfers an electron to another atom
Explanation:
An ionic bond is also called as the electrovalent bond. It is a type of linkage that is formed by the electrostatic attraction formed between ions of opposite charge in a chemical compound.
These bonds are formed when the valence electrons from one of the atom are transferred to the another atom.
