1.

How did the eukaryotic cell develop organelles -which was missing in prokaryotes-
which were the first organisms on earth?

The development of organelles in eukaryotic cells, which are absent in prokaryotes, is a key
evolutionary event, and it is thought to have occurred through processes like endosymbiosis and
membrane infolding.

1. Endosymbiosis Hypothesis:
o This theory suggests that organelles such as mitochondria and chloroplasts
originated from ancient symbiotic relationships between primitive eukaryotic cells
and prokaryotic cells.
o Early eukaryotic ancestors engulfed smaller prokaryotes (likely bacteria) through
a process similar to phagocytosis. Instead of digesting these prokaryotes, a
symbiotic relationship formed. The engulfed bacteria eventually became
mitochondria (in the case of aerobic bacteria) and chloroplasts (in the case of
photosynthetic bacteria).
o Mitochondria and chloroplasts have their own DNA, which is similar to bacterial
DNA, supporting this hypothesis.
2. Membrane Infolding Hypothesis:
o Some organelles, such as the nucleus, endoplasmic reticulum, and Golgi
apparatus, are thought to have arisen through the infolding of the plasma
membrane of a primitive prokaryotic cell.
o Over time, the plasma membrane of the early eukaryotic cell may have folded
inward, creating internal compartments that eventually specialized into distinct
organelles. For example, the nucleus likely formed when the cell membrane
folded around the genetic material, creating a protective compartment.

Together, these processes helped eukaryotic cells evolve into more complex structures with
compartmentalized functions, which gave them distinct advantages, such as the ability to
regulate metabolic processes more efficiently.
 2. Give the ethical and legal issues of using stem cell.

Ethical Issues:

1. Embryonic Stem Cell Research:

o Destruction of embryos: Destroying human embryos for research is
controversial, as many believe life begins at conception.
o Moral status of the embryo: Debates arise over whether embryos have the same
moral status as humans.
o Alternative sources: Adult and iPSCs are alternatives but less versatile than
embryonic stem cells.
2. Informed Consent:
o Donor rights: Transparent, informed consent is critical when collecting stem
cells.
o Exploitation of vulnerable populations: There’s a risk of exploiting donors,
especially economically disadvantaged women.
3. Cloning and "Designer Babies":
o Reproductive cloning: Ethically concerning due to issues of identity and
potential abuse.
o Genetic enhancement: Raises concerns about inequality and commodifying life.
4. Equity and Access:
o Access to treatment: High costs may limit access, leading to inequity.
o Exploitation of patients: Unregulated stem cell therapies can exploit vulnerable
patients.
5. Animal Rights:
o Ethical concerns arise over the use of animals in stem cell research.

Legal Issues:

1. Regulation of Embryonic Stem Cell Research:

o Varying national laws: Different countries have varying legal frameworks, with
some allowing and others banning such research.
o Public funding: Government funding for research involving embryos is restricted
in many regions.
2. Intellectual Property:
o Patents: Ownership of stem cell lines raises debates over patentability and
biopiracy concerns.
3. Stem Cell Clinics and Fraud:
o Regulation: Many unregulated clinics offer unsafe and unproven treatments.
o Accountability: Legal issues arise over harm caused by such therapies.
4. Therapeutic Cloning:
o Legal ambiguity: Some countries permit therapeutic cloning for research, while
others ban it.
5. Gene Editing:
 o CRISPR: Combining gene-editing and stem cells raises legal concerns about
modifying human embryos.
6. Clinical Trials and Approval:
o Regulation: Rigorous trials are required, but some clinics bypass these, raising
safety and legal issues.
 3. Human genome project – found the complete sequence of 46 chromosomes - using
this information what can be done?

The Human Genome Project (HGP) successfully mapped the entire sequence of the 46 human
chromosomes, which represents the complete set of genetic material in humans. This vast
repository of genetic information has numerous potential applications across various fields,
including medicine, biotechnology, and anthropology. Here are some key ways this information
can be used:

1. Personalized Medicine
o Tailored treatments: Individual genetic profiles enable customized drugs and
therapies.
o Pharmacogenomics: Analyzing genetic markers predicts drug responses,
enhancing effectiveness and minimizing adverse reactions.
2. Disease Prevention and Risk Assessment
o Genetic predispositions: Identifying gene mutations linked to diseases like cancer
and diabetes helps assess risk.
o Early diagnosis: Genetic testing allows for early detection and intervention.
3. Gene Therapy
o Correcting disorders: Targeting defective genes can treat genetic disorders, such
as cystic fibrosis and sickle cell anemia.
o CRISPR technology: Precision gene-editing tools enable modification of faulty
genes.
4. Cancer Research and Treatment
o Targeted therapies: Understanding cancer mutations facilitates therapies that
specifically attack cancer cells.
o Personalized treatments: Tailoring cancer therapies to an individual’s genetic
profile enhances effectiveness.
5. Ancestry and Evolutionary Studies
o Tracing ancestry: Genome comparisons reveal human evolution and migration
patterns.
o Population genomics: Studies genetic diversity and evolutionary pressures across
populations.
6. Forensic Science
o Identification techniques: Genetic sequencing improves identification in criminal
cases and paternity testing.
o Genealogy searches: Genomic data establishes familial relationships.
7. Agricultural and Biotechnological Applications
o Crop and livestock improvement: Insights from human genetics enhance yield and
disease resistance in agriculture.
 o Synthetic biology: Genome data aids in designing new organisms for various
applications.
8. Understanding Rare and Genetic Diseases
o Identifying causes: Genome analysis helps pinpoint genetic mutations responsible
for rare diseases.
9. Ethical, Legal, and Social Implications
o Informed decision-making: Genome sequencing supports health and lifestyle
choices based on genetic information.
o Privacy concerns: Increased genetic data raises issues of privacy, data security,
and potential discrimination, highlighting the need for ethical frameworks.
 4. Justify why structure of a protein determines the function of the protein.

 Specificity of Binding:

 Proteins bind to specific molecules (ligands, substrates) at precisely shaped binding sites.
For instance, enzymes fit substrates at their active sites like a key in a lock; any structural
change can impair binding and function.

 Stability and Folding:

 Proper folding into a three-dimensional shape is essential for stability. Misfolded proteins
can lead to diseases like Alzheimer's and cystic fibrosis, demonstrating the importance of
structure in maintaining function.

 Allosteric Regulation:

 Proteins can change shape when a molecule binds at a site other than the active site,
affecting their function. For example, hemoglobin alters its conformation upon oxygen
binding, enhancing oxygen transport.

 Protein-Protein Interactions:

 Many biological processes depend on specific protein interactions, such as in signal

transduction pathways. Structural changes in these proteins can disrupt binding and
cellular signaling.

 Structural Proteins:

 Proteins like collagen and keratin provide structural support; their function relies on their
ability to form specific shapes. Structural changes can weaken their mechanical
properties.

 Enzymatic Catalysis:

 Enzymes catalyze reactions by orienting substrates optimally; the shape of the active site
is crucial for stabilizing transition states. Alterations in structure can lead to loss of
activity.

 Membrane Proteins:

 Proteins embedded in cell membranes depend on their structure for functions like
transport and signaling. Disruptions can hinder interactions with membranes or signaling
molecules.
 Antigen-Antibody Interactions:

 Antibodies recognize and bind to specific antigens due to the unique structure of their
variable regions. Structural changes can impair their ability to neutralize antigens,
affecting immune response