Answer:
Menstruation, the follicular phase, ovulation and the luteal phase.
Explanation:
Menstruation, the follicular phase, ovulation and the luteal phase are the four events or phases of the menstrual cycle. Luteinizing hormone, follicle-stimulating hormone, and the female sex hormones i.e. estrogen and progesterone are the types of hormones that controls the uterine cycle. Each event in the uterine cycle has its own significance in the female body.
Answer:
El híbrido va a ser esteril.
Explanation:
En la cruza entre dos especies distintas, cuando ocurre, existen distintos mecanismos de aislamiento reproductivo, que son barreras que inhiben o interrumpen el flujo génico entre especies distintas. Es decir que no habrá exito reproductivo de estas cruzas. Se trata de caracteres biológicos propios de cada especie que previenen la reproducción con otras especies.
Estos mecanismos de aislamiento reproductivo pueden ser precigóticos o postcigóticos.
1.Pre-copulatorios o pre-cigóticos:
- Ecológico o por aislamiento de hábitat;
- Por incompatibilidad de gametas.
2. Post-copulatorios o cigóticos:
- Inviabilidad del híbrido;
- Híbrido con viabilidad o fertilidad disminuido;
- Interacciones citoplasmáticas.
La mula es producto de la cruza entre dos especies distintas: una yegua (Equus ferus caballus) y un burro (Equus africanus asinus). Es un ejemplo de la accion de mecanismo poscigótico, en el cual se forma un híbrido viable esteril. Este ejemplar puede nacer, crecer y sobrevivir, pero que no puede producir gametas funcionales, por lo cual no puede reproducirse.
It is 19.3g/cm^3. To find density, you divide mass by volume, or d=m/v
Answer:
It's 3!
Explanation:
There must be genetic differences so the best fitted organisms will survive. If they were all the same then no one would be best fitted and Natural Selection wouldn't be able to occur
It's not 1 because a food shortage isn't required, there's always competition for food sources
It's not 2 because there doesn't need to be a change in the environment for natural selection, just for evolution.
And it can't be 4 if 1 and 2 are wrong!
Hope this helped!
Answer:
Some species are similar in structure because they are evolved from the same ancestors while some differences are also present in them due to the changes occurs in the body because of adaptation to environmental conditions.
Grizzly bears and sea otters have canine teeth because canine teeth are used to crushing hard food materials such as fishes and shells.
Explanation:
Canine teeth are present in the grizzly bear and sea otters due to eating of food materials which are hard. Canine teeth used to crush the food materials.
