Sance Démarche 1 Je rappelle les besoins des cellules.

Tatiana [17]

Answer:

There are many invasive animal sand plants which are harmful for native flora and fauna. Some of the invasive or alien species are as following:

1. The Nile Perch: Nile Perch is a type of fish which is native to African lake and river systems but if it is introduced in other countries lake it can be dangerous to other fishes in that lake. It was earlier introduced to Lake Victoria but after sometime it was evaluated that native fishes got extinct and the Nile Perch become very huge in size.

2. The cotton whitefly: Cotton whitefly are native to India but now can be found on most of the continents and have very bad impact on the fauna or agricultural plants. They have capability of transmitting upto 100 different plant viruses. find them thriving

3. The desert locust: The desert locust is a species of locust which can fly and are one of the most disastrous migratory pests in the world. They feed over green green vegetation, including pasture, crops and fodder. They have very bad impact on native flora as they are migratory pests. They are found in Africa and migrated to nearby countries such as India and damages the native flora.

4. European starlings: European starlings are the bird species which fight with native species for food and shelter. They are found in Alaska and Mexico and proved invasive in U.S. as the number of native birds decreased with their introduction.

4 0

3 years ago

PLEASE HELLPPP

Scorpion4ik [409]

Of the given possible statements, the one that best supports that a newly discovered species is that the animal's body temperature increased when the ambient temperature increased. An exothermic animal relies on eternal temperatures to keep warm and so a rise in ambient temperatures would cause a rise in internal temperatures of the animal. Therefore, the answer is a.

5 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. Different clinical conditions are the result of this nondisjunction.

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

3 years ago

Laboratory Re

oksian1 [2.3K]

1. Number of chromosomes in the parent cell is 46

2. Number of chromatids in daughter cells formed by first division is 46

3. Number of chromosomes in daughter cells formed by first division is 23

4. Number of chromosomes in daughter cells of second division 23

5. Number of haploid cells formed by meiotic division of parent cell is 4

4 0

3 years ago

A student recorded the height of each student in the school. She then made a bar graph of her results. She observed

eimsori [14]

Answer:

Height is affected by multiple pairs of genes on different chromosomes.

Explanation:

The quantitative traits are those whose inheritance pattern is the result of the action of multiple genes that act together with the environment. The distribution of quantitative traits in the population follows a bell-shaped curve, which is referred to as normal distribution or Gaussian distribution. These traits are 'quantitative' because they vary among individuals in the population to produce a continuous range of phenotypic values. Examples of quantitative traits include, among others, metabolic rate, height, and weight.

6 0

3 years ago