Answer:
When homologous chromosomes form pairs during prophase I of meiosis I, crossing-over can occur. Crossing-over is the exchange of genetic material between homologous chromosomes. It results in new combinations of genes on each chromosome. It is obviously another source of genetic variation in offspring.
Hope this helps you. Do mark me as brainliest.
A geologist studies rocks and such
The names of the respiratory structures involved include the following: nasal cavities (or oral cavity) > pharynx > trachea > primary bronchi (right & left) > secondary bronchi > tertiary bronchi > bronchioles > alveoli.
<h3>What is respiration?</h3>
Respiration is defined as the oxygenation of blood through the intake of oxygen and the removal of carbon dioxide.
The pathway of oxygen gas molecule from the surrounding air through the respiratory system to the blood include respectively the following:
- Nasal cavities (or oral cavity): This has a direct association with the outside oxygen from the environment.
- pharynx: This so also called the throat.
- trachea: This is also called the wind pipe.
- Primary bronchi (right & left): This divides from the trachea to form two bronchi.
Learn more about respiration here:
brainly.com/question/2809259
#SPJ1
When cell over divide they cause a sickness or cancer
