Answer:
Answer Below
Explanation:
It usually occurs every 3 to 5 years but can occur as low as every 2 years or as long as every 7 years.
Answer: 1. Protostome development./2. Bilateral symmetry/4. Three embryonic germ layers
Explanation:
Over 600 million years ago some animals invaded aquatic and terrestrial environments in the pre-Cambrian period. These animals were enforced by huge evolutionary irradiation, and now they occupy every environment on planet Earth. From tiny insects and crustaceans smaller than 1mm in length to giant crabs from Japan that can reach 3m (with open legs), the arthropods are found in all size models, with an estimated number of more than one million species described. Concerning characteristics they are - Bilateral, triploblastic( Three embryonic germ layers), prostomial. Internally and externally segmented body, divided into at least two regions, head, and abdomen; typically with a cephalic shield or carapace. Opened circulatory system; the dorsal heart is a muscle pump with lateral Ostia for blood return.
When you cross two heterozygotes with the genotype Aa, the offspring will be: <span>Parents: Aa x Aa</span>
<span>F1 generation: AA Aa Aa aa</span>
<span>This means that ½ of the offspring will be heterozygous, ¼ will be homozygous (dominant) and ¼ will be homozygous (recessive).</span>
Answer:
The correct answer is D. Umbilical cord
Explanation:
The umbilical cord connects the fetus to the placenta and through it exchanges nutritional substances as well as oxygen-rich blood. The umbilical cord is maintained throughout gestation until the moment of birth, when it is cut and leaves a permanent scar, the navel. The umbilical cord is responsible for breathing and feeding the fetus until the moment it is born, so any failure or blockage in the circulation of oxygen and nutrients through the cord can lead to injury or even death of the embryo. It also serves to remove waste and carbon dioxide (CO2).
