BIO 182 EXAM 3 2026 CELLULAR PROCESSES
TEST PAPER QUESTIONS SOLUTIONS GRADED
A+
◉ Fertilization.
Answer: Sperm penetrates protective layer of egg
Receptors on egg surface bind to molecules on sperm surface
Egg surface prevent polyspermy
◉ Polyspermy.
Answer: fertilization by more than one sperm
◉ Acrosomal Reaction.
Answer: Reaction that is triggered when the sperm meets the egg.
The acrosome tip of the sperm releases hydrolytic enzymes that
digest material around the egg. Actin filaments reach down to
connect to sperm-binding receptors. Sodium rushes to the gaps as
the plasma membrane of the sperm and egg fuse to depolarize the
voltage of the plasma membrane. This happens in mere seconds.
◉ Cortical Reaction.
Answer: Slow Block to Polyspermy. Calcium from cortical granules
fill up the gap formulated when the vitelline layer lifts up and
,detaches from the egg, ripping off the sperm-binding receptors in
the process. The vitelline layer becomes a fertilization envelope,
which acts as a slow block to polyspermy.
◉ What does the rise in calcium within the cytosol aid with?.
Answer: Increases rates of cellular respiration and protein synthesis,
activating the egg due to rapid changes in metabolism
◉ Proteins and mRNAs are needed for activation, which is already
present in the egg. What then merges?.
Answer: The sperm nucleus and the egg nucleus
◉ Fertilization in Mammals.
Answer: Sperm travels through follicle cell layer that surrounds the
egg. It then reaches the zona pellucida (Ex. matrix), triggering the
cortical reaction. This type of fertilization is relatively slow.
◉ Developmental Stages.
Answer: Cleavage, Gastrulation, Organogenesis
◉ Cleavage.
Answer: rapid cell division WITHOUT growth. Consists of formation
of blastomeres (smaller cells) and blastocoel once the zygote
becomes a blastocoel
,◉ Blastocoel.
Answer: fluid-filled cavity of the blastula
◉ Blastula.
Answer: hollow ball of cells
◉ Vegetal Pole.
Answer: More yolk
◉ Animal Pole.
Answer: "animal" part, less yolk
◉ Gray crescent in frogs.
Answer: in frog after fertilization, it becomes gray crescent;
individual cells could develop into a normal frog only if it contained
a portion of these
◉ Cleavage in Frog Embryo.
Answer: From 2-cell stage to Blastula. The size stays the same.
◉ Holoblastic Cleavage.
, Answer: Complete division
Little yolk
Sea urchins, frogs, mammals
◉ Meroblastic Cleavage.
Answer: Incomplete division
More yolk (yolk-rich)
Reptiles, birds, egg-laying animals
◉ What comes after fertilization?.
Answer: Cleavage?
◉ What comes after cleavage?.
Answer: Morphogenesis
◉ Morphogenesis Parts.
Answer: Gastrulation and Organogenesis
◉ Morphogenesis.
Answer: process by which cells occupy their appropriate locations
◉ Gastrulation.
TEST PAPER QUESTIONS SOLUTIONS GRADED
A+
◉ Fertilization.
Answer: Sperm penetrates protective layer of egg
Receptors on egg surface bind to molecules on sperm surface
Egg surface prevent polyspermy
◉ Polyspermy.
Answer: fertilization by more than one sperm
◉ Acrosomal Reaction.
Answer: Reaction that is triggered when the sperm meets the egg.
The acrosome tip of the sperm releases hydrolytic enzymes that
digest material around the egg. Actin filaments reach down to
connect to sperm-binding receptors. Sodium rushes to the gaps as
the plasma membrane of the sperm and egg fuse to depolarize the
voltage of the plasma membrane. This happens in mere seconds.
◉ Cortical Reaction.
Answer: Slow Block to Polyspermy. Calcium from cortical granules
fill up the gap formulated when the vitelline layer lifts up and
,detaches from the egg, ripping off the sperm-binding receptors in
the process. The vitelline layer becomes a fertilization envelope,
which acts as a slow block to polyspermy.
◉ What does the rise in calcium within the cytosol aid with?.
Answer: Increases rates of cellular respiration and protein synthesis,
activating the egg due to rapid changes in metabolism
◉ Proteins and mRNAs are needed for activation, which is already
present in the egg. What then merges?.
Answer: The sperm nucleus and the egg nucleus
◉ Fertilization in Mammals.
Answer: Sperm travels through follicle cell layer that surrounds the
egg. It then reaches the zona pellucida (Ex. matrix), triggering the
cortical reaction. This type of fertilization is relatively slow.
◉ Developmental Stages.
Answer: Cleavage, Gastrulation, Organogenesis
◉ Cleavage.
Answer: rapid cell division WITHOUT growth. Consists of formation
of blastomeres (smaller cells) and blastocoel once the zygote
becomes a blastocoel
,◉ Blastocoel.
Answer: fluid-filled cavity of the blastula
◉ Blastula.
Answer: hollow ball of cells
◉ Vegetal Pole.
Answer: More yolk
◉ Animal Pole.
Answer: "animal" part, less yolk
◉ Gray crescent in frogs.
Answer: in frog after fertilization, it becomes gray crescent;
individual cells could develop into a normal frog only if it contained
a portion of these
◉ Cleavage in Frog Embryo.
Answer: From 2-cell stage to Blastula. The size stays the same.
◉ Holoblastic Cleavage.
, Answer: Complete division
Little yolk
Sea urchins, frogs, mammals
◉ Meroblastic Cleavage.
Answer: Incomplete division
More yolk (yolk-rich)
Reptiles, birds, egg-laying animals
◉ What comes after fertilization?.
Answer: Cleavage?
◉ What comes after cleavage?.
Answer: Morphogenesis
◉ Morphogenesis Parts.
Answer: Gastrulation and Organogenesis
◉ Morphogenesis.
Answer: process by which cells occupy their appropriate locations
◉ Gastrulation.
