The female gametophyte structure that produces eggs in nonvascular plants are called archegonia. The male structure that produces sperm are called antheridia. A gametophyt â¦ e is the part of the plant that is responsible for creating gametes AKA sexual reproductive cell (sperm or egg).
All American Express cards begin with '37,' followed by currency indicator (digits 3, 4), account number (digits 5-11), card number within account (digits 12-14), and check digit (digit 15).
Best Answer: The first digit is always 3, 4, 5 or 6. Credit card companies use a standardized system of assigning numbers. 3 means it is an American Express or Diners Club credit card. Credit cards beginning with 4 means that it is a Visa card. If your credit card numbers starts with 5 it represents a MasterCard. And in the case of a credit card number beginning with 6, it is a Discover credit card. The other numbers are used to carry various other information.