Biology Exam Questions and Answers

Exam
Name
University Affiliation
Module One
Question One
Growth is the quantitative increase in the physical size and mass of a specific organism over a given time while development is a process where an individual organism changes itself from a single cell into a more complex multicellular organism; it is both qualitative and quantitative.
Question Two
The zygote is the first stage of life and comes to creation when a new organism is created through sexual reproduction after the union of the male and female gametes. It is formed immediately after fertilization. The embryo is a multicellular diploid eukaryote in its earliest stage of development. The cells begin to differentiate at this point.
Question Three
A frog has two hemispheres the animal pole later forms the ectoderm and mesoderm and the vegetal pole that forms the endoderm and contains the nutrient that protects and nourishes the embryo.
Question Four
The tadpole stage is immediately after hatching. They develop skin and teeth. The other stage is a young frog. The frog has only a small tail tub, and it leaves the water and only returns when it wants to lay eggs.
Question Five
Embryo homology refers to the intrinsic similarity that indicates a common evolutionary origin. For instance, the bird`s wings, the seal`s flipper and the forelegs of a cat.
Question Six
Embryo analogy means similarity of the general function or the superficial appearance. For example, both snakes and fish have scales. The two types of scale differ in their embryonic origin.
Question Seven
Teratogens are agents or factors that may produce physical or functional malformation of the human embryo or fetus that the mother may be exposed to while pregnant. An example is a drug such as cocaine.
Module 2
Question One
The Von Leeuwenhoek's hypothesis is by a Dutch scientist who used a small microscope in his study of sperms of several animals. He discovered that only one sperm was needed in the creation of life. He argued that the sperm and not the egg are the essential factors in reproduction. He believed that the sperm was responsible for the formation of an embryo.
Question Two
Mammalian female reproductive tract influences sperm motility through (1) Muscular contraction uterus: It enhances the passage of sperm through the uterine cavity. (2) The reservoir in the fallopian tube: They store sperm in a fertile state by interacting with the oviductal epithelium. (3) Secretion of thermotaxis and chemotaxis: they guide the sperms toward the oocyte. (4) The structure of the cervix: it provides a receptive environment for sperm entry after ejaculation.
Question Three
The sea urchin is used in the experiment because of: (1) their fertilization is external hence easy to observe. (2) Their male and female gametes follow the typical structure of other animals concerning features hence key in studying the process. (3) The transparency of the urchins' eggs enables them to be used actually to see that the sperm cell fertilizes the ova.
Question Four
External fertilization in sea urchins explains chemotaxis. The egg initiates the process by releasing chemoattractants. The sp...