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.
Hypospadias is a condition in males where the opening of the urethra is a the bottom of the penis. This results in the following complications which should be reported immediately:
<span>
When the temperature is greater than 101 °F
Excessive bleeding (some spotting or blood stains on the dressing is normal)
Extreme irritability
Excessive pain
Increasing redness of the penis
Disinterest in eating and drinking (particularly after 24 hours)
Continuous vomiting
Change in urination
Difficulty urinating (pushing when he urinates)</span>
Explanation : x = 79 marks
The marks scored by Mike on four math test are 88,91,75 and 72.
Average of marks, A = 81
Let in fifth test he scores x marks.
The formula for finding average is :
In the fifth test he scores 79 marks.
Hence, this is the required solution.
The answer is applying sustainable development.
The trend of declining ecosystem resource availability and increasing demand for these resources can best be countered by applying sustainable development. Sustainable development refers to the development in which the needs in the present is meet without compromising the future generation's ability to meet their own needs.
