Science

Refine Search

Why do red blood cells have no nucleus?

Red blood cells look like flat disks that travel around the body in blood vessels. They carry oxygen to tissues and remove carbon dioxide from them. Hemoglobin plays an important role in red blood cells, because it carries the oxygen that nourishes cells and takes away carbon dioxide to prevent it from accumulating in cells.\nIn the mature form, red blood cells, or erythrocytes, do not have nuclei; however, they have not always been without nuclei. In their immature forms, red blood cells did have nuclei. An intermediate form of red blood cells, called a normoblast, expels its nuclei as the am..

Continue Reading

Are both lungs in the human body the same size?

The left lung contains two lobes and an indentation named the cardiac notch, which is situated on the lung's medial surface for the apex of the heart. The lungs are made up of soft and spongy tissue and take up the majority of the space in the thoracic cavity. Both lungs are encased by a dual-layered serous membrane, named the pleura.

Continue Reading

What are some names of harmful microorganisms?

All bacteria, most protozoa and some fungi are microorganisms. The term "microorganisms" is used to indicate a life form that is not visible to the human eye without the aid of a microscope. These may be a single cell or made up of many cells. There are microorganisms in every type of environment on Earth, but there are more beneficial microorganisms than there are harmful ones. Genetic engineering involves manipulation of microorganisms to create specific characteristics in larger organisms.

Continue Reading

How many types of minerals are there?

Minerals are naturally occurring solids formed by geological processes. Water is not considered a mineral in its liquid form, but its ice form is considered the most common mineral on the Earth's surface.\nMineral grains accrete to form rocks, which comprise the solid ground of our planet. A rock can have several minerals in its composition or just one. Granite contains quartz, albite and orthoclase, while sandstone compromises just quartz.

Continue Reading

What is a slogan related to sulfur?

Sulfur, also spelled sulphur, is one of the most notorious elements, and several humorous slogans have been penned that relate to its disagreeable or interesting attributes. "Sulphur: without it, rotten eggs would just smell like a dead chicken." "It is the color yellow and it is really stinky, But only if in compounds, and, no, not in a Twinkie." "Sulfur: the element that painted Yellowstone." Each of these slogans was originally authored by an unknown writer.

Continue Reading

How many moles of water are in a liter?

Molarity is found by dividing the number of moles of a substance present by the size of the sample. Most often, it is used to find the concentration of a solute in an aqueous solution. For example, a mole of sodium chloride dissolved in 1 liter of solution has a molarity of 1 mole per liter. Pure water is not a solution, so molarity is found by dividing grams per liter by grams per mole, giving an answer expressed in moles per liter.

Continue Reading

What do lymph vessels do?

To ensure lymph moves in one direction, lymph vessels have valves that prevent back-flow. Lymphatic fluid consists of proteins, minerals and other nutrients. It passes through a number of lymph nodes before being drained into venous circulation. Lymph nodes help to get rid of damaged cells in the body, as well as cancer cells, infectious organisms and other foreign material.

Continue Reading

How do plant cells divide?

Before mitosis, the plant cell goes through an interphase, in which DNA is synthesized and genes are transcribed and gather to form the nucleolus. During prophase, chromosomes are condensed, the nuclear membrane disintegrates and spindle poles move to opposite ends of the spindle. Spindle microtubules are formed that attach to the centromeres of the chromosomes. In metaphase, chromosomes line up along the equator of the cell.\nAnaphase occurs in two parts. In anaphase A, sister chromatids separate at the centromeres. Then in anaphase B, the chromatids are pulled apart towards opposite poles as..

Continue Reading

What is the molar mass of KCI03?

The molar mass of either compound can be calculated by adding together the atomic mass of each atom of each element comprising the compound. For example, a compound containing one atom of potassium and one atom of chlorine includes at least the mass of 39.09 grams per mole for a potassium atom and 35.45 grams per mole for a chlorine atom.

Continue Reading

What is the hottest time of the day?

When the sun rises, the part of the Earth receiving its light does not warm up immediately. Rising temperatures, or thermal response, at the planet's surface is delayed. For example, though sunrise happens early during summer months, the highest temperature of the day typically occurs during mid-afternoon. Because sunrise is later in the winter, the interval between solar noon and the hottest part of the day is often later in the afternoon.

Continue Reading
Showing 8911 to 8920 of 10000 (1000 Pages)