Answer:
el niño tendría síndrome de downEl síndrome de Down es causado por un error aleatorio en la división de las células que tiene como resultado la presencia de una copia extra del cromosoma 21.
Answer:
b.
Explanation:
They used Franklin's photo to determine that DNA was a double helix.
Answer:
a. Heterozygous individuals may pass on their copy of the disease-causing allele to offspring.
Explanation:
Tay-Sachs, which is a recessive lethal disease ---- Let say the recessive lethal diseases is s
∴ it only results when an individual posses two copies of the diseases-causing allele i.e two copies of the disease will be ss.
Now, when two hetrozygous individuals crossed , it is obvious that each can pass on their copy of the disease-causing allele to the offspring.
Let show an illustration for the above statement.
Let the heterozygous individual be Ts, if Ts cross with another Ts;
we will have:
Ts × Ts
T s
T TT Ts
s Ts ss
the offspring are TT,Ts,Ts,ss
We can now see how the Heterozygous individuals pass on their copy of the disease-causing allele to the offspring (Ts).
Answer:
B. often use tube feet to move around in their environment
Explanation:
Tube feet are tiny tubular projections of echinoderms on the underside (oral side). They are a member of the echinoderm water vascular system.
Tubular feet are used for feeding, breathing and shifting. They are arranged around the sides, in grooves. They work by hydraulic pressure. They are used to transfer food in the centre to the oral mouth, and may stick to surfaces. Tube feet allow certain animals to stick and travel slowly to the ocean floor. for example starfish uses tube feet for the above functions.
Hence, the correct option is B.
