1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
faltersainse [42]
3 years ago
7

Down syndrome is caused by __________, resulting in three copies of chromosome 21.

Biology
2 answers:
scZoUnD [109]3 years ago
6 0
Down syndrome is caused by nondisjunction, resulting in three copies of chromosome 21. (Normally we just have two)

Hope this helps~
iren [92.7K]3 years ago
5 0
<span> the error occurs at random during the formation of an egg or sperm.</span><span>Down syndrome is caused by a random error in cell division

</span>
You might be interested in
Give a scenario where a cell may need to perform a form of endocytosis
Elanso [62]
Endocytosis is the process where a cell imports large things into the cell. All forms of endocytosis are active, meaning the cell expends ATP while performing this process. Specifically, a style of endocytosis called phagocytosis involves a cell surrounding the target material with its cell membrane and encloses it while bringing it into the cell.  This enclosed membrane bound material then pinches off into a spherical 'vesicle'.  An example of this can be a cell importing a protein into its cellular space.
6 0
3 years ago
What reaction takes place in the stroma
Vlada [557]
<span>The reaction that takes place in the stroma is collectively known as the Calvin Cycle. The stroma is responsible for the 2nd stage of photosynthesis where ATP and NADPH are used to capture and reduce carbon dioxide in the plant cell.</span>
<span>
It is a fluid-like organelle that surrounds the grana within the chloroplast in plant cells. The stroma is also responsible for storing chloroplast DNA and chloroplast ribosomes where molecular processes like replication and transcription/translation of chloroplast proteins occur.</span>
8 0
3 years ago
Explain why lizards with brown tails are more likely to be eaten by snakes than the lizards with blue tails.
Alina [70]

Answer:

lizard tails with vivid blue reflectance evolved in communities with either weasel or snake predators, which can both detect blue wavelengths. However, lizard tail UV reflectance was much higher in populations with only snake predators, perhaps because snakes can detect UV, yet weasels cannot. Finally, a cryptic brown tail evolved on islands where birds are the primary lizard predator. Because birds have keen visual acuity, a brown, camouflaged tail may be more advantageous.

Explanation:

7 0
2 years ago
An example of a properly functioning homeostatic control system is seen when
ANEK [815]

Answer:

the kidneys excrete salt into the urine when dietary salt levels rise

Explanation:

Hyponatremia is an electrolyte imbalance, with a low level of sodium in the blood. The normal value of sodium in adults is 136 to 145 mEq / L. Sodium is an element, or electrolyte of the blood. Sodium chloride is commonly known as table salt.

Certain conditions can cause decreased sodium in the blood. Specific causes of hyponatremia include:

Water poisoning (water replacement without electrolyte replacement).

Problems in the kidneys, heart or liver.

Medications: such as diuretics, Heparin, certain chemotherapeutics (Aminoglutethimide, Cyclophosphamide and Vincristine).

Conditions related to steroids, hormones or metabolic defects, such as a syndrome that alters the secretion of antidiuretic hormone (SSIHA). If this occurs, you urinate frequently and the kidneys excrete too much sodium. This can result from many conditions, including certain types of lung cancer.

6 0
3 years ago
Understanding the human genome has allowed us to?
telo118 [61]

Answer:

The human genome is a complete set of nucleic acid sequences for humans, encoded as DNA within the 23 chromosome pairs in cell nuclei and in a small DNA molecule found within individual mitochondria. These are usually treated separately as the nuclear genome and the mitochondrial genome.

4 0
3 years ago
Other questions:
  • The absence of ________ leaves obligate anaerobes susceptible to killing by oxygen.
    13·1 answer
  • What are the quick protective reactions that occur within your nervous system called?
    6·1 answer
  • How was central florida before nasa and the kennedy space center?
    5·1 answer
  • If a person has the values for an objects density and volume , what value can be calculated
    12·2 answers
  • How many years of education you have to do for a plant worker?
    8·1 answer
  • How many rotations dose the moon take every time it orbits around earth
    8·1 answer
  • Franklin Delano Roosevelt (FDR) was born in Hyde Park, New York. He was the thirty-second president of the United States. He was
    7·2 answers
  • What body system are capillaries from? Provide evidence from the internet. (This can be a short sentence lol)
    7·1 answer
  • PLSS HELP IMMEDIATELY!!!! ILL MARK BRAINIEST IF U DONT GUESS OR LEAVE LINKS<br> !!!!!
    7·2 answers
  • During DNA replication, what occurs?
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!