B2 (Cells: membranes & membrane transport, Organelles & Compartmentalization, Cell specialization)

Question 1

Membranes & Membrane Transport.

Diffusion & Osmosis:

Answer 1

Passive transport of substances across membranes.

Question 1

Membranes & Membrane Transport.

Phospholipid Bilayer:

Answer 1

Forms cell membranes.

Question 2

Membranes & Membrane Transport.

Active Transport:

Answer 2

Requires energy; against concentration gradient.

Question 3

Organelles & Compartmentalization.

Nucleus:

Answer 3

Contains genetic material

Question 4

Organelles & Compartmentalization.

Mitochondria:

Answer 4

Site of cellular respiration. (ATP synthesis)

Question 5

Organelles & Compartmentalization.

Endoplasmic Reticulum:

Answer 5

Rough (ribosomes)

and

smooth (lipid synthesis).

Question 6

Cell Specialization.

Tissues:

Answer 6

groups of cells with similar functions.

Question 7

Cell Specialization.

Organs & Organ Systems:

Answer 7

Combinations of tissues working together.

Question 8

Cell Specialization.

Stem Cells:

Answer 8

Undifferentiated cells with the potential to become specialized.

Question 9

Discuss the role of the sodium-potassium pump in maintaining the resting membrane potential of a neuron. Include the ion movements involved.

Answer 9

The sodium-potassium pump goes through cycles of shape changes (to help maintain a negative membrane potential.)

In each cycle, three sodium ions exit the cell, while two potassium ions enter the cell.

These ions travel against the concentration gradient, so this process requires ATP.

Question 10

Explore the functional significance of the endoplasmic reticulum in protein synthesis. How does the rough endoplasmic reticulum (RER) differ from the smooth endoplasmic reticulum (SER) in terms of function?

Answer 10

SER: creation/ storage of lipids and steroids,

RER: synthesis of various proteins.

The RER is termed “rough” due ribosomal attachments to the surface compared to the SER, which does not have ribosomes

Question 11

Investigate the ethical considerations surrounding the use of stem cells in medical research and treatment. Highlight potential benefits and challenges.

Answer 11

Ethical considerations:
Source of Stem Cells: Balancing the use of embryonic and adult stem cells.
Therapeutic vs. Reproductive Cloning: Ethical concerns regarding medical vs. reproductive applications.
Informed Consent: Ensuring donors understand implications.
Equitable Access: Avoiding socioeconomic disparities.

Benefits:
Regenerative Medicine: Repairing tissues and organs for degenerative diseases.
Disease Modeling: Studying diseases for targeted treatments.
Drug Testing: Improving drug safety through stem cell testing.
Personalized Medicine: Tailoring treatments based on genetics.

Challenges:
Tumorigenicity: Risk of tumor formation from stem cells.
Immunological Rejection: Addressing host rejection of transplanted cells.
Ethical Concerns: Balancing benefits with ethical considerations.
Unintended Consequences: Understanding long-term effects and unintended outcomes.
Technical Challenges: Overcoming hurdles in controlled stem cell differentiation.

Question 12

Name the term based off of the definition

Definition: Simultaneous transport of two substances across a membrane using a carrier protein.

Answer 12

Term: Cotransport

Question 13

What is the function of membrane proteins

Answer 13

Functions: Transport, enzymatic activity, signal transduction, cell adhesion, and recognition.

Question 14

Totipotent Stem Cells

Answer 14

Definition: Cells with the potential to differentiate into any cell type, including embryonic and extraembryonic cells.

Significance: Early-stage cells in embryonic development.

Question 15

Pluripotent Stem Cells

Answer 15

Definition: Cells with the potential to differentiate into any cell type but not extraembryonic cells.

Role: Intermediate stage in cellular differentiation.