Term 3 Chapter 5.1 Flashcards
What is DNA? And explain the structure of the DNA.
DNA: Dioxyribo Nucleic Acid
DNA is a chemical that contains information about an organism’s growth and functions.
DNA is a blueprint of an organism.
The DNA is a helical molecule which means a twisted ladder.
DNA is made of a very long chain of nucleotides.
It makes our chromosomes and stores our genetic information.
DNA is made of two strands of molecules joined in a structure that resembles a twisted ladder or a double helix structure.
What is a gene?
A gene is a portion of the DNA that makes the protein.
Explain the shape of the chromosome and how many pairs of chromosomes does the human body have.
A chromosome is shaped like two strands held together at the centromere, x like shape. A chromosome consists of two identical structures called chromatids held together near the center by a structure called a centromere.
A human body has 46 chromosomes (23 pairs)
What are the three main parts nucleotides are composed of?
- A phosphate group
- A 5 carbon sugar
- A nitrogen base
Name the four base pair and their combination in the double helix structure.
Adenine - Thymine
Cytosine - Guanine
Who was the first scientist who modeled the DNA molecule?
Watson & Crick
What is the role of nucleotides?
Nucleotides hook together to make the sugar-phosphate backbone of the DNA.
What is chromatin?
Chromatin - loose mass of strands. They bound the proteins.
Why do chromosomes condense and replicate?
Chromosomes condense and replicate to become a perfect copy.
Definition and the importance of cell division,
The process of cell dividing and creating two new cells is known as cell division. Cell division is involved in growth, development and repair
Explain how cell division is involved in the growth, development and repair of an organism.
Growth: Larger organisms have more cells because the ratio of the surface area and volume is limited.
Development: During development, cells become specialized, and take a different shape to perform particular functions.
Repair: As cells age, and die or simply wear out, cell division makes new cells.
