Answer:
Chromosomes were first named by cytologists viewing dividing cells through a microscope. The modern definition of a chromosome now includes the function of heredity and the chemical composition. A chromosome is a DNA molecule that carries all or part of the hereditary information of an organism. In eukaryotic cells, the DNA is packaged with proteins in the nucleus, and varies in structure and appearance at different parts of the cell cycle.
Explanation:
Cells reproduce genetically identical copies of themselves by cycles of cell growth and division. The cell cycle diagram on the left shows that a cell division cycle consists of 4 stages:
G1 is the period after cell division, and before the start of DNA replication. Cells grow and monitor their environment to determine whether they should initiate another round of cell division.
S is the period of DNA synthesis, where cells replicate their chromosomes.
G2 is the period between the end of DNA replication and the start of cell division. Cells check to make sure DNA replication has successfully completed, and make any necessary repairs.
M is the actual period of cell division, consisting of prophase, metaphase, anaphase, telophase, and cytokinesis.
Regarding the order rhizobiales of the class Alphaproteobacteria, the genus that includes human pathogens is Brucella.
Rhizobiales are a type of Alphaproteobacteria, which are a type of Proteobacteria, which are Gram-negative bacteria.
Brucella is also a type of Gram-negative bacteria that can cause brucellosis, which is an infectious disease caused by eating unpasteurized milk or undercooked meat.
Answer:
Sunlight and heat react with gases in the atmosphere.
Explanation:
Smog forms purely as a result of air pollution.
Gases released from machines on earth rise up the sky.
The risen gases then meet and react with the sun plus fine particles in the atmosphere, smog forms.
Smog causes a lot of problems on earth among them being:
- Accidents due to the blurry effect causedv by smog on roads thereby distructing drivers.
Answer:
eubacteria and archaebacteria
