Complete the sentence by putting a cross (X) in the box next to your answer - Edexcel - GCSE Biology - Question 5 - 2013 - Paper 1
Question 5
Complete the sentence by putting a cross (X) in the box next to your answer.
Sperm cells and egg cells contain sex chromosomes.
Egg cells contain
A one X chromosom... show full transcript
Worked Solution & Example Answer:Complete the sentence by putting a cross (X) in the box next to your answer - Edexcel - GCSE Biology - Question 5 - 2013 - Paper 1
Step 1
Complete the sentence by putting a cross (X) in the box next to your answer.
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Answer
Egg cells contain C two X chromosomes.
Step 2
Complete the Punnett square to show how the sex of a child is inherited.
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Answer
The Punnett square would be filled out as follows:
X (Mother)
X (Mother)
Y (Father)
XY
XY
X (Father)
XX
XX
This indicates that there is a 50% chance for each sex.
Step 3
Calculate the percentage chance that a child will be female.
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Answer
The percentage chance that a child will be female is 50%.
Step 4
Using the information in the diagram and your own knowledge, describe the stages of the menstrual cycle.
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Answer
The menstrual cycle can be described in several stages:
Menstruation (Day 1-5): The cycle begins with menstruation, which is the shedding of the uterine lining.
Follicular Phase (Day 6-14): After menstruation, the uterine lining starts to rebuild. Follicles develop in the ovaries, leading to ovulation around Day 14.
Ovulation (Day 14): A mature egg is released from the ovary.
Luteal Phase (Day 15-28): After ovulation, the uterine lining is thickened and maintained to prepare for a fertilized ovum. If the ovum is not fertilized, the lining will eventually shed.
Step 5
Explain what happens to the uterus lining if a woman becomes pregnant.
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Answer
If a woman becomes pregnant, the uterus lining is maintained and thickened to support the developing embryo, preventing menstruation from occurring.
