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2 years ago

Identify the lettered muscle responsible for depressing the eye and turning it laterally.

1 answer:

8 0

The extraocular or extrinsic eye muscles, considering their relatively small size, are incredibly strong and efficient. There are the six<span> extraocular muscles, which act to turn or rotate an eye about its vertical, horizontal, and antero-posterior axes: medial rectus (MR), lateral rectus (LR),</span>

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Imagine that a given species has a gene for hair color (B = dominant brown, b = recessive white) and a gene that controls hair l

serg [7]

Answer:

Phenotypes: All Brown Hair Color and All Short Hair Length

Genotypes:

Homozygous dominant hair color and homozygous dominant hair length: (BBSS, BBSS, BBSS, BBSS).

Homozygous dominant hair color and heterozygous hair length: (BBSs, BBSs, BBSs, BBSs)

Heterozygous hair color and homozygous dominant hair length: (BbSS, BbSS, BbSS, BbSS)

Heterozygous hair colour and heterozygous hair length: (BbSs, BbSs, BbSs, BbSs)

Explanation:

Hair color :

B = dominant brown

b = recessive white

Hair length :

S = dominant short

s = recessive long

The dihybrid cross between parents with the genotypes:

BBSS × BbSs

If BBSS self crossed; we have the following traits= BS, BS, BS, BS

If BbSs self crossed; we have the following traits= BS, Bs, bS, bs

The dihybrid cross is as follows:

BS BS BS BS

BS BBSS BBSS BBSS BBSS

Bs BBSs BBSs BBSs BBSs

bS BbSS BbSS BbSS BbSS

bs BbSs BbSs BbSs BbSs

Phenotypes = All Brown Hair Color and All Short Hair Length

Genotypes include:

Homozygous dominant hair color and homozygous dominant hair length: (BBSS, BBSS, BBSS, BBSS).

Homozygous dominant hair color and heterozygous hair length: (BBSs, BBSs, BBSs, BBSs)

Heterozygous hair color and homozygous dominant hair length: (BbSS, BbSS, BbSS, BbSS)

Heterozygous hair colour and heterozygous hair length: (BbSs, BbSs, BbSs, BbSs)

7 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

Which has higher air pressure—warm air or cold air? How do you know?

Masja [62]

The one with higher air pressure is Warm Air. The reason why is because when you boil water, the water always makes the lid rise. This is because Warm Air has more activity in its atoms and molecules, so it is moving around more, which in turn means that there is more pressure.

Hope I helped. :)

7 0

2 years ago

Xylem is a plant tissue made up of elongated cells stacked end to end the length of the plant's stem. How does xylem help a plan

Eddi Din [679]

Answer:

Ur dad

Explanation:

Ur dad

6 0

2 years ago

Which is a lymphocyte

Ann [662]

It is A a cell also knows as white cell

3 0

2 years ago

Read 2 more answers