Review the key concepts, formulae, and examples before starting your quiz.
🔑Concepts
The process of reproduction begins with the fusion of a sperm and an ovum to form a single-celled structure called the .
The undergoes repeated cell division (mitosis) as it moves down the oviduct to form a ball of hundreds of cells known as the .
The travels to the uterus and gets embedded in its thick, vascular wall; this process is called .
Once the is implanted, it continues to grow and develop specialized tissues and organs. This process is known as .
The stage of the embryo in which all the distinct body parts (such as hands, legs, head, eyes, and ears) can be identified is called the .
In humans, the period of development from fertilization to the birth of the baby is called the period, which lasts approximately months or days.
Animals that give birth to young ones (like humans, cows, and dogs) are called animals, whereas those that lay eggs are .
📐Formulae
💡Examples
Problem 1:
Explain the transformation from a to an .
Solution:
The is a single cell formed by the fusion of nuclei. It begins to divide repeatedly into cells. These cells soon begin to form groups that develop into different tissues and organs of the body. This developing structure is termed an .
Explanation:
The change is primarily marked by a transition from a unicellular state to a multicellular state through the process of rapid cell division.
Problem 2:
Differentiate between an and a .
Solution:
An is the early stage of development where body parts are not yet identified. A is the later stage of development where all body parts can be clearly identified.
Explanation:
The primary distinction is the level of morphological and the visibility of limbs and organs.