Help Biology Homework

Biology homework help!?

Please help answer these questions if you can:

1. Are chromosomal abnormalities confined only to certain parts of the body? Explain your answer.

2. Are genetic defects associated with abnormalities of autosomes or of sex chromosomes? Explain your answer.

3. Formulate a question that could be answered by observing chromosomes of different species of animals.

4. Why would it be much more difficult to construct a karyotype of unstained chromosomes?

5. Which pair of chromosomes can contain two very different chromosomes and still be considered normal? Explain your answer.

Biology homework!! please help!!!!!!!?

Eukaryotic cells, in general, are more sophisticated at the following types of transport:

(1) Protein targeting. Protein targeting or protein sorting is the mechanism by which a cell transports proteins to the appropriate positions in the cell or extracellularly. Sorting targets can be the inner space of an organelle, any of several interior membranes, the cell's outer membrane, or its exterior via secretion or exocytosis. This delivery process is carried out based on information contained in the protein itself. Correct sorting is crucial for the cell; errors can lead to diseases.

(2) Ion channels. Ion channels are pore-forming proteins that help establish and control the small voltage gradient across the plasma membrane of all living cells by allowing the flow of ions down their electrochemical gradient. They are present in the membranes that surround all biological cells.

(3) Translocons. The translocon (commonly known as a translocator or translocation channel) is the complex of proteins associated with the translocation of nascent polypeptides across membranes. In eukaryotes the polypeptides are transported into the interior (cisternal or luminal) space of the endoplasmic reticulum (ER) from the cytosol. This process requires the protein to cross a hydrophobic lipid bilayer. In prokaryotes, a similar protein complex transports polypeptides across the plasma membrane. Bacterial pathogens can assemble translocons in their host membranes, allowing them to export virulence factors into their target cells.

SecY protein is main transmembrane subunit of eubacterial protein secretory pathway and protein-secreting ATPase complex, also known as translocon. Secretion across the inner membrane in Gram-negative bacteria occurs via the preprotein translocase pathway. Proteins are produced in the cytoplasm as precursors, and require a chaperone subunit to direct them to the translocase component. From there, the mature proteins are either targeted to the outer membrane, or remain as periplasmic proteins. The translocase protein subunits are encoded on the bacterial chromosome.

(4) In eukaryotic cells, the electron transport system is located in the inner membrane of the mitochondria. In prokaryotic cells, the electron transport system is located in the cytoplasmic membrane.

Please help with biology homework?

1.a. The deamination of amino acids form the nitrogen group of urea
2.c. Osmo- means solute concentration causing diffusion of water
3.a. The osmoreceptors would increase thirst because there's more Na
4.c, ADH will increase water reabsorption. If the blood is dilute, the hypothalamus will decrease ADH secretion which cause increased urine.
5.a. The only one of those choices that's correct.
6.d. The only one that's correct. Increased ADH increases the permeability of the distal nephron and collecting duct to water increasing the reabsorption and decreasing urine volume.

Please help Biology homework question!?

Imagine that four people are infected with HIV from a common source (an infected blood sample). Initially, the patients' HIV populations are genetically identical. By the time they develop full-blown AIDS, how would the viral populations of the four patients compare?


a.)Each patient's viral population would be unique, specifically adapted to deal with—and overcome—his or her unique immune system responses.





b.)The viral populations would still be genetically identical to each other and would be unchanged from the time of infection.





c.)The viral populations would have evolved to a new and more dangerous strain, but that strain would be identical across all four patients. This is the strain of virus found in every person suffering full-blown AIDS.

Biology Homework- Mendel& Heredity HELP!!!!!!?

Problem:
The offspring of the cross between a plant with purple flowers and a plant with white flowers are 23 plants with purple flowers and 26 plants with white flowers. Use the letter P for purple and p for white. What are the genotypes of the parent plants. Explain your answer.

(explain clearly& simply please)
:]

PLEASE help, biology homework questions...?

Why is the location of DNA within the nucleus a potential problem for protein synthesis? How does RNA solve this problem for the cell?

AND

Explain how the process of copying DNA into messenger RNA is similair to DNA replication. Include:
double helix, enzymes, subunits, base sequence


If you know either please help me, Im desperate!!

Can someone help me with my human biology homework?

1. when the sperm and ova create a zygote. they both are gametes that contain the haploid number of cells. so together they make a diploid cell.

2.
DIFFERENCES

meiosis: reduces chromosome number by half
produce germ-line cells
undergoes two divisions
occurs in gonads

mitosis: results identical daughter cells
produce somatic cells
undergoes one division

SIMILARITES:
- both undergo DNA replication
- both undergo interphase, prophase, metaphase, anaphase
- both begin with the same number of chromosomes
- both processes involve a spindle

3. metaphase during mitosis is when the homologous double-stranded chromosomes line up on top of each other along the equator

in meiosis it undergoes metaphase TWICE. um firstly the double-stranded homologous chromosomes line up side by side and split off into separate cells right. and then now there is one of each chromosome in separte cells. these chromosomes then line up on top of each other on the equator in metaphse II
occurs in somatic cells (normal body cells)