am i adopted because i dont have my parents hair color

Your hair color doesn't necessarily come from your parents, it could be from your grandparents or great grandparents or so on

why do they get down syndrome.

If they have an extra chromosome 21 it causes down syndrome

Why do they have different alleles, or versions, of those genes?

"During meiosis, homologous chromosomes line up and recombination occurs between them. This results in gametes with unique combinations of alleles on each chromosome and therefore unique individuals."

Is it possible for human offspring to only get 10% of the genes from their parents?

Yes... but only due to a HUUGE mutation. Just a 2% differentiation in gene structure can create a whole new species. Hope this helps.

Also,why is the last pair of chromosomes in the picture labeled "X"? Why didn't they just number it 23?

it is the human sex chromosomes so it determines your sex boy or girl. for more info go to lesson 4:Reproduction and genetic variation

why are they green and red?

That's just how they look under an X-ray.

Main content

Middle school biology - NGSS

Course: Middle school biology - NGSS > Unit 7

Lesson 1: Chromosomes

Chromosome pairs

Google Classroom

Review your understanding of chromosome pairs in this free article aligned to NGSS standards.

Key points:

Every species has its own specific number of chromosomes. For example, humans have 46 chromosomes in a typical body cell.
Many species have chromosomes that come in matched pairs. For example, the 46 chromosomes in a human cell can be organized into 23 pairs.
These paired chromosomes are called homologous chromosomes. Homologous chromosomes are the same size and shape.
Homologous chromosomes contain the same genes. However, they may have different alleles, or versions, of those genes.
Scientists and medical professionals can use a karyotype to view an organism’s sets of chromosomes. In a karyotype, pairs of homologous chromosomes are arranged next to each other. This makes it easier to see if there are any differences between chromosomes that may lead to a genetic condition.

Want to join the conversation?

Sort by:

PierceS
Posted a year ago. Direct link to PierceS's post “why do they look like bac...”
why do they look like bacon
Button navigates to signup pageComment on PierceS's post “why do they look like bac...”
(26 votes)
Answer
- Jimmy
  Posted a year ago. Direct link to Jimmy's post “i luv bacon bro”
  i luv bacon bro
  Comment on Jimmy's post “i luv bacon bro”
  (6 votes)
avalegg
Posted a year ago. Direct link to avalegg's post “am i adopted because i do...”
am i adopted because i dont have my parents hair color
Button navigates to signup pageComment on avalegg's post “am i adopted because i do...”
(13 votes)
Answer
- Rishi Patel
  Posted a year ago. Direct link to Rishi Patel's post “Your hair color doesn't n...”
  Your hair color doesn't necessarily come from your parents, it could be from your grandparents or great grandparents or so on
  Comment on Rishi Patel's post “Your hair color doesn't n...”
  (16 votes)
owen.junck
Posted a year ago. Direct link to owen.junck's post “why do they get down synd...”
why do they get down syndrome.
Button navigates to signup pageButton navigates to signup page
(5 votes)
Answer
- SomewhatSadit
  Posted a year ago. Direct link to SomewhatSadit's post “If they have an extra chr...”
  If they have an extra chromosome 21 it causes down syndrome
  Button navigates to signup page
  (10 votes)
8559818278
Posted a year ago. Direct link to 8559818278's post “why does it look like bac...”
why does it look like bacon?
Button navigates to signup pageComment on 8559818278's post “why does it look like bac...”
(5 votes)
Answer
- David
  Posted 21 days ago. Direct link to David's post “cuz ur hungry”
  cuz ur hungry
  Button navigates to signup page
  (1 vote)
IsabellaG
Posted a year ago. Direct link to IsabellaG's post “why are they green and re...”
why are they green and red?
Button navigates to signup pageComment on IsabellaG's post “why are they green and re...”
(2 votes)
Answer
- Adonalsium
  Posted a year ago. Direct link to Adonalsium's post “That's just how they look...”
  That's just how they look under an X-ray.
  Comment on Adonalsium's post “That's just how they look...”
  (7 votes)
joshua wolford
Posted a year ago. Direct link to joshua wolford's post “Why do they have differen...”
Why do they have different alleles, or versions, of those genes?
Button navigates to signup pageButton navigates to signup page
(3 votes)
Answer
- jenna renes
  Posted a year ago. Direct link to jenna renes's post “"During meiosis, homologo...”
  "During meiosis, homologous chromosomes line up and recombination occurs between them. This results in gametes with unique combinations of alleles on each chromosome and therefore unique individuals."
  Button navigates to signup page
  (5 votes)
AMARW
Posted 6 months ago. Direct link to AMARW's post “Is it possible for human ...”
Is it possible for human offspring to only get 10% of the genes from their parents?
Button navigates to signup pageButton navigates to signup page
(3 votes)
Answer
- Tyler
  Posted 6 months ago. Direct link to Tyler's post “Yes... but only due to a ...”
  Yes... but only due to a HUUGE mutation.
  Just a 2% differentiation in gene structure can create a whole new species.
  Hope this helps.
  Button navigates to signup page
  (5 votes)
Tiara Forbes
Posted a month ago. Direct link to Tiara Forbes's post “Also,why is the last pair...”
Also,why is the last pair of chromosomes in the picture labeled "X"? Why didn't they just number it 23?
Button navigates to signup pageButton navigates to signup page
(3 votes)
Answer
- Peril14 [online]🐉
  Posted a month ago. Direct link to Peril14 [online]🐉's post “it is the human sex chrom...”
  it is the human sex chromosomes so it determines your sex boy or girl. for more info go to lesson 4:Reproduction and genetic variation
  Comment on Peril14 [online]🐉's post “it is the human sex chrom...”
  (5 votes)
27kimchri
Posted 8 months ago. Direct link to 27kimchri's post “What is the rarest gene”
What is the rarest gene
Button navigates to signup pageButton navigates to signup page
(5 votes)
Answer
Wolfy
Posted a year ago. Direct link to Wolfy's post “The reason why they look ...”
The reason why they look odd is because of the light they are looking at the chromosomes under, think about when they take an X-Ray of a bone, everything becomes black and white.
Button navigates to signup pageButton navigates to signup page
(4 votes)
Answer