Could their be a fourth statement to cell theory?

All life must maintain an internal balance, despite environmental changes. What is this called?

stepladder [879]

This is called homeostasis.

5 0

3 years ago

What happens in your body to cause you to get a fever?

andriy [413]

The presence of a fever is usually related to stimulation of the body's immune response. Fever can support the immune system's attempt to gain advantage over infectious agents, such as viruses and bacteria, and it makes the body less favorable as a host for replicating viruses and bacteria, which are temperature sensitive. Infectious agents are not the only causes of fever, however. Amphetamine abuse and alcohol withdrawal can both elicit high temperatures, for example. And environmental fevers--such as those associated with heat stroke and related illnesses--can also occur.

The hypothalamus, which sits at the base of the brain, acts as the body's thermostat. It is triggered by floating biochemical substances called pyrogens, which flow from sites where the immune system has identified potential trouble to the hypothalamus via the bloodstream. Some pyrogens are produced by body tissue; many pathogens also produce pyrogens. When the hypothalamus detects them, it tells the body to generate and retain more heat, thus producing a fever. Children typically get higher and quicker fevers, reflecting the effects of the pyrogens upon an inexperienced immune system.

4 0

3 years ago

Predict phenotypes associated with nondisjunction of sex chromosomes.

Mnenie [13.5K]

Answer: The new daughter cells will have an abnormal amount of genetic material. That is called aneuploidy and it is the presence of an abnormal number of chromosomes. Different clinical conditions are the result of this nondisjunction.

Explanation:

Normal cells are diploids, that means they have two copies of each gene, one of each chromosome. So normal cells have two homologous chromosomes, one from each parent.

During anaphase of cell division, each pair of chromosomes is separated by the mitotic spindle. The separated chromosomes are then pulled by the spindle to opposite poles of the cell, and eventually will end up in the new daughter cells.

Nondisjunction is the failure of homologous chromosomes to separate properly during cell division, so it is the miss segregation of them. The new daughter cells will have an abnormal amount of genetic material. <u>Different clinical conditions are the result of this nondisjunction.</u>

Sex chromosomes participates in sex determination of an individual. Females have two X chromosomes (XX), while males have one X and one Y chromosome (XY) So nondisjunction of sex chromosomes could be:

XX: one cell with no chromosome and the other cell with two X chromosomes.
XY: one cell with no chromosomes and the other cell with XY chromosomes.

According to which gametes are fused during fertilization, different phenotypes can be given. For example, if a gamete with one chromosome fuses with another gamete with two chromosomes, the result will be an individual with three chromosomes (it could be XXY, or XXX) called trisomy.

Triple X syndrome is characterized by an extra X chromosome in females. Those affected are often taller than average, but most females have a normal sexual development. Klinefelter syndrome is known XXY individuals, and it causes infertility in males, breast growth, less body hair and weaker muscles.

And if a gamete with no chromosome fuses also with another gamete with no chromosome, the result is a nullisomy. But due to the lack of genetic material, the nullisomic gametes are rendered unviable for fertilization.

And if a gamete with no chromosome fuses with another gamete with one chromosome (normal) the result is a monosomy, the presence of only one chromosome from a pair. The result can be an individual who is X or Y. People with Turner syndrome have one X chromosome and it is the only monosomy that is seen in humans because other cases monosomy are lethal.

Any of those examples is called aneuploidy and it is the presence of an abnormal number of chromosomes.

3 0

2 years ago

4. Monosaccharides are to polysaccharides as

vova2212 [387]

Answer:

C

Explanation:

C

8 0

2 years ago

The temperature in the upper atmosphere is -2°C, and the temperature on Earth’s surface is 5°C. Which type of weather is most li

kogti [31]

Alright, so the highest temperature at which water is most dense id 4 degrees Celcius, if it gets lower than that, water would start to expand. So at 5 degrees, it would just be rain.

6 0

2 years ago