Earth’s magnetic field is generated by the?

aalyn [17]

Scientist study index fossils so they will get an understanding of what life was like back then.

5 0

2 years ago

The highlighted structure separates the oocyte from the externally located ________. zona pellucida primary follicle corona radi

Naya [18.7K]

Answer:

Granulosa cells

Explanation:

Foliculogenesis is a dynamic and complex process through which the follicle goes through many stages of development in a short period (approximately 60 days in humans and some chimpanzees).

The stages classification is based on morphological changes such as follicular size or diameter, the number of follicular cell layers, etcetera. These classifications might vary among authors but could be denominated as:

Primordial follicle

Primary follicle

Secondary follicle and

De Graaf follicles (This is the one shown in the image)

Through each stage, there are certain modifications in the oocyte, follicular cells, and connective tissue. As the oocyte grows, the follicular cells might reach a size twice or three times bigger than the ones of the primordial follicles. Their shape also changes and they adopt an aspect of stratified epithelium. Their cytoplasm gets a granulous aspect, after what these cells receive the name of granulous cells. The De Graaf follicle characterizes for having a space named follicular antro that displaces the oocyte to one of the sides.

The oocyte at this point gets surrounded by zona pellucida and corona radiata .

The follicular antro (The highlighted structure) separates the oocyte from the externally located granulosa cells or follicular cells.

7 0

2 years ago

Questions

Marat540 [252]

The decay of uranium isotopes is used to provide information about the age of Earth.

<h3>Explanation:</h3>

Isotopes of Uranium U-232, U-233 , U-234 , U-235 , U-236 , U-238 are used as fuel in nuclear reactors or as explosives for nuclear weapons. Uranium 238 is not very radioactive and it constitutes for nearly 99.3% of natural uranium on Earth and has the longest lifetime: its period is 4.5 billion years, about the age of Earth.

Use of radiometric dating techniques help in defining the age of substances (natural or man-made) using the known decay rates of radioactive elements. Each element has an individual decay rate and half life time.

Two Uranium isotopes (U-238 and U-235) are used for radiometric dating. Both the isotopes have different decay rates and half life period. Both are unstable and radioactive. Since two different isotopes produce two different decay clocks (one as a reference to other), it is beneficial in accurately determining the age of samples. The age of earth (rocks or other natural elements) can be easily determined using Uranium isotopes.

4 0

2 years ago

What is the ability of some creatures to control their body temperatures through internal means such as muscle shivering, fat bu

marusya05 [52]

Endothermic is the answer

8 0

2 years ago

Read 2 more answers

A closed system is best characterized as a system in which: (3 points)

Anarel [89]

Answer:

A closed system is a physical system that does not allow transfer of matter in or out of the system, though, in different contexts, such as physics, chemistry or engineering, the transfer of energy is or is not allowed.

7 0

2 years ago