43 terms

The nucleus controls the functions of life


Terms in this set (...)

Cell Membrane
a thin, protective covering that separates the inside of a cell from its external environment and controls the flow of materials into and out of the cell.
Cell Wall
a tough, rigid structure that surrounds the cell membrane of plant cells.
a jelly-like substance that contains the organelles and other life-supporting materials, such as water and sugar.
a specialized cell part that carries out specific functions to ensures a cell's survival.
are organelles that are specialized to provide energy for cells by changing sugar called glucose into usable energy.
organelles in plant cells that trap the energy from the sun and make glucose as an energy source for the plant.
an organelle without a membrane that produces proteins.
are essential materials required for the cell to carry out the activities necessary for its survival.
Endoplasmic Reticulum
a network of membrane-covered channels within a sell.
are membrane-covered sacs that form off the ends of the endoplasmic reticulum.
Golgi Body
an organelle that sorts and packages proteins for transport.
are membrane-covered storage containers within cells.
the organelle that controls all the activities of the cell parts described above.
Nuclear Membrane
the thin outer membrane that surrounds the cell nucleus; separates the contents of the nucleus from the cytoplasm.
a membrane-free organelle that floats in the interior of the nucleus and makes ribosomes.
Nuclear Pores
openings in the nuclear membrane that allow only certain materials into and out of the nucleus.
the material that contains the information that determines inherited characteristics.
What does DNA stands for?
deoxyribonucleic acid
What is DNA backbone made of?
sugar and phosphate
How many chromosomes total in a human cell nucleus?
How many pairs?
What are the 4 nucleotide bases?
A (Adenine), G (Guanine), C (Cytosine), and T (Thymine)
How does the nucleotide bases match up?
A-T and C-G
What is the chromosal difference between male and females?
in males, the 23rd pair of chromosomes is the XY pair. In females, it is the XX pair.
What is a gene?
genes are small segments of DNA located at specific places on a chromosomes. (They code for protein).
Gene Therapy
insert a missing gene or repair a defective gene in human cells.
How many bases make up a codon?
3 bases make up the codon
What is the difference between DNA and mRNA?
In mRNA instead of T its U and mRNA can fit through the nuclear pore and DNA can't.
What does the ER and Golgi do to the protein?
>The endoplasmic reticulum acts as a transport system for materials made in the cell.
>The golgi body sorts and packages proteins for transport.
Who did an experiment that showed that 3 bases of DNA code for a single amino acid in the genetic code?
Francis Crick and his buddy Sydney Brenner in 1961.
What is a mutation?
Mutation is when the normal order of bases gets changed.
What are the 3 types of Mutation?
Deletion, Substitution and Addition
Deletion Mutation
when one base gets deleted and is missing.
Substitution Mutation
when one base is changed for another.
Addition Mutation
when one extra base gets added to the code.
Neutral Mutation
does not affect the organism.
Positive Mutation
gives an organism advantage over other organisms.
Negative Mutation
will be a disadvantage and the organism may not live.
What is the difference between a positive and negative mutation?
the positive mutation benefits an organism, while the negative mutation harms an organism or reduces the probability that organisms with the mutation can produce offspring or survive in their environment.
What is a mutagen?
are substances of factors that can cause mutations in DNA.
Define enzymes
proteins that help speed chemical reactions within cells.
Define hormones
substances, such as proteins, released from specific glands to control particular cellular activities such as growth.
How is a protein produced
> the nucleus receives a chemical signal to make a specific protein.
> the DNA message for a specific protein is copied into a small molecule called ribonucleic acid or RNA.
> RNA leaves through a nuclear pore.
> the RNA message is delivered to the ribosome makes the protein.
> the manufactured protein enters the endoplasmic reticulum.
> a vesicle forms off the end of the endoplasmic reticulum and carries the protein to the Golgi Body.
> the Golgi body repackages the protein for transport out of the cell.
> a vesicle forms off the end of the Golgi body to carry the protein to the cell membrane.
> the vesicle attaches to the cell membrane, and its protein contents are released out of the cell.