Chapter 4.1 Flashcards
(20 cards)
What are the 4 things that the master set of instructions in the nucleus determine?
- What each will become
- How each cell with function
- When will each cell grow and divide
- When each cell will die
What does DNA stand for?
Deoxyribonucleic Acid
What is the function of DNA?
Carries the instructions for cell function
What does DNA look like?
A twisted ladder
AKA Double Helix
What is DNA made up of?
- the sides of the ladder are made of phosphate and sugar
2. the steps of the ladder are made of 4 nitrogen bases
What are the 4 nitrogen bases?
A - Adenine
G - Guanine
C - Cytosine
T - Thymine
What is a DNA message?
The arrangement of nitrogen bases on the DNA
How do the bases always join together?
A always pairs up with T.
G always pairs up with C.
In what form does DNA exist in the nucleus?
Chromatin
What is within each strand of chromatin?
One molecule of DNA
What happens to the chromatin when the cell is ready to divide?
The chromatin coils up into compact, x-shaped chromosomes
How many chromosomes does a human have?
46 (23 pairs)
How do you determine the gender/sex?
The 23rd pair of chromosomes determines the sex.
Male = XY
Female = XX
Where are genes located?
Specific places on a chromosome, every chromosome carries thousand of genes
What do genes do?
Store the information needed to produce different proteins
Your skin and muscle cells contain identical DNA. How are these cells able to function differently?
Each cell contains identical DNA but only specific genes are “read” in each cell to produce specific proteins.
By making specific proteins, a cell becomes specialized to carry out a particular function.
What are enzymes and hormones?
Specialized proteins
How are proteins produced?
- Nucleus receives a chemical signal to make a specific protein
- DNA message for a specific protein is copied into a small molecule called RNA
- RNA leaves through a nuclear pore
- RNA message is delivered to the ribosome and the ribosome makes the protein
- Manufactured protein enters the endoplasmic reticulum
- Vesicle forms off the end of the endoplasmic reticulum and carries the protein to the golgi body
- Golgi body repackages protein for transport out of the cell
- Vesicle forms off the end of the golgi body to carry the protein to the cell membrane
- Vesicle attaches to the cell membrane and its protein contents are released out of the cell
What does RNA stand for?
Ribonucleic acid
What is chromatin?
A substance that contains DNA and proteins
