All AP Biology Resources
Example Questions
Example Question #1306 : Ap Biology
Which of the following processes allows for the fusion of the genetic material of the sperm and egg?
Mitosis
Meiosis I
All of meiosis
Meiosis II
Mitosis
After sperm cell and oocyte plasma membrane fusion, the sperm pronucleus moves into the oocyte cytoplasm. The sperm and egg pronuclei migrate towards the center of the cell while performing DNA replication, where both nuclear membranes dissolve. The chromosomes are prevented from dispersing by a mitotic spindle that tethers the maternal and paternal genetic material together. The cell then begins mitosis, which fuses the genetic material into a single diploid genome.
Example Question #1307 : Ap Biology
Which of the following features of egg activation releases the egg from the metaphase II meiotic arrest?
Cortical granule exocytosis
Hyaline layer formation
Intracellular calcium release
Fusion of sperm and oocyte plasma membrane
Intracellular calcium release
During oogenesis, specifically ootidogenesis, the secondary oocyte halts development and arrests its growth at metaphase II of meiosis. This arrest is maintained through ovulation until fertilization in the fallopian tube. During fertilization, the cortical reaction in the oocyte acts as the slow block to polyspermy and starts with the release of intracellular calcium. This release of calcium ions allows the egg to resume meiosis and ends the metaphase II arrest.
Example Question #1308 : Ap Biology
Which of the following characteristics is not true regarding the fast block to polyspermy?
It is a faster block for the many sperm surrounding the egg
It is an electrical block
There is an influx of calcium ions
The egg develops a positive charge
There is an influx of calcium ions
The fast block to polyspermy is the initial method that prevents polyspermy by the large number of sperm cells surrounding the egg. The fast block is triggered by sperm binding, which initiates a change in membrane potential. There is a large influx of sodium ions into the egg, creating a depolarization event that prevents further sperm penetration.
Example Question #111 : Reproductive System
Which of the following best represents a difference between the fast and slow blocks to polyspermy?
Sperm cells can overcome the fast block to polyspermy but not the slow block
Fast block involves sodium ion transport and the slow block involves calcium ion transport
None of these
The fast block involves an increase in intracellular ion concentration and the slow block does not
Fast block involves sodium ion transport and the slow block involves calcium ion transport
Both the fast and slow blocks to polyspermy prevent the penetration of a second sperm cell into the oocyte. The fast block to polyspermy is the initial and immediate block upon sperm binding. The fast block is an electrical block caused when oocyte membrane depolarization is started by an influx of calcium ions. The slow block is characterized by a change in zona pellucida makeup through the cortical reaction, which prevents sperm cell binding. The cortical reaction is triggered by the release of intracellular calcium.
Example Question #1309 : Ap Biology
Which of the following best describes how dizygotic twins are produced?
Nondisjunction
Fertilization of one egg by two sperm
Two eggs are released and fertilized
One zygote splits into two embryos during development
Two eggs are released and fertilized
Dizygotic twins are produced by the release and fertilization of two separate egg cells. Both zygotes implant in the uterus and develop. The resulting twins will not be genetically identical because they arise from different gametes.
Example Question #112 : Reproductive System
Which of the following best describes how monozygotic twins are produced?
Two eggs are released and fertilized
Nondisjunction
One zygote splits into two embryos during development
Fertilization of one egg by two sperm
One zygote splits into two embryos during development
Monozygotic twins are produced when a zygote divides into two embryos. This process is spontaneous and may result from blastocyst collapse. The resulting twins are genetically identical because they are produced from the same gametes.
Example Question #1312 : Ap Biology
If polyspermy does occur, which of the following symptoms will the resulting organism exhibit?
The offspring will experience stunted physical growth
The offspring will develop learning disabilities
The zygote is inviable
The offspring will possess developmental delays
The zygote is inviable
Polyspermy, or the fertilization of an egg by more than one sperm cell, creates an inviable zygote that will not develop.
Example Question #342 : Systems Physiology
Which of the following choices does not cause infertility?
Low semen quality
Ovulation problems
Alcohol use
Sexually transmitted diseases
Alcohol use
Infertility is the inability to reproduce. There are many causes for infertility and many unexplained cases. The causes include sexually transmitted diseases, ovulation problems, and low semen quality.
Example Question #1314 : Ap Biology
During the process of fertilization, what does the term "syngamy" refer to?
Pronuclei membrane degradation
The fusion of two genomes
Cortical granule formation
Fast block to polyspermy
The fusion of two genomes
"Syngamy" is a term that refers to the joining of two genomes during fertilization. This occurs through the first mitotic division of the zygote, after the membranes of the pronuclei dissolve.
Example Question #31 : Understanding Other Reproductive Physiology
Which of the following definitions does the term “menarche” refer to?
When menstrual periods begin in human females
Implantation of the embryo in human females
When menstrual periods stop in human females
Contractions preceding vaginal delivery
When menstrual periods begin in human females
“Menarche” is the term that refers to the onset of menstrual bleeding in female humans. The timing of menarche is influenced by variety of factors including genetics and environmental factors. Age of menarche is typically between 12 to 15 years old.