Biology Topic 1: Cell Biology Flashcards
What are the main components of plant and animal cells?
Cell membrane, cytoplasm, genetic material enclosed in a nucleus
Eukaryotic cells have these structures.
What distinguishes bacterial cells from eukaryotic cells?
Bacterial cells are smaller, have a cell membrane surrounded by a cell wall, and their genetic material is a single DNA loop without a nucleus
They may also contain plasmids.
List the sub-cellular structures found in most animal cells.
- Nucleus
- Cytoplasm
- Cell membrane
- Mitochondria
- Ribosomes
These structures are essential for various cellular functions.
What additional parts do plant cells have compared to animal cells?
- Chloroplasts
- Permanent vacuole filled with cell sap
- Cell wall made of cellulose
The cell wall provides strength to the cell.
What is the purpose of using estimations in cell biology?
To judge the relative size or area of sub-cellular structures
Estimations can help in understanding scale.
What is required for the practical activity of observing cells under a microscope?
Use a light microscope to observe, draw, and label plant and animal cells with a magnification scale included
This helps in understanding cell structure.
What is cell specialization?
Cells may be specialized to carry out a particular function
Examples include sperm cells, nerve cells, muscle cells, root hair cells, xylem, and phloem cells.
Explain the importance of cell differentiation.
Cells differentiate to form different types of cells as an organism develops
Most animal cells differentiate early; many plant cells can differentiate throughout life.
What is the role of chromosomes in a cell?
Chromosomes carry genes and are normally found in pairs in body cells
They are made of DNA molecules.
Describe the stages of the cell cycle.
Cells grow, increase sub-cellular structures, DNA replicates, and then divides into two identical cells
Mitosis is a key part of this process.
What is a stem cell?
An undifferentiated cell capable of giving rise to many more cells of the same type and from which certain other cells can arise from differentiation
They play crucial roles in development and tissue repair.
What are some potential uses of stem cells in medicine?
- Treatment for diabetes
- Treatment for paralysis
- Cloning for medical treatment
Therapeutic cloning can help create compatible cells for patients.
What are the risks associated with stem cell use?
- Transfer of viral infection
- Ethical or religious objections
These issues must be considered in medical research.
How do bacteria multiply?
By simple cell division known as binary fission
They can divide as often as every 20 minutes under optimal conditions.
What is the formula for calculating magnification?
Magnification = size of image / size of real object
This formula is used in microscopy.
Fill in the blank: Plant and algal cells have a cell wall made of _______.
cellulose
This structure is important for cell strength.
True or False: All types of animal cells differentiate at an early stage.
False
Many plant cells retain the ability to differentiate throughout life.
What is the significance of using aseptic techniques in culturing microorganisms?
To prepare uncontaminated cultures for investigating the action of disinfectants and antibiotics
It ensures accurate results in experiments.
How can the cross-sectional area of colonies be calculated?
Using the formula πr²
This calculation helps in studying bacterial growth.
What is the primary function of mitochondria?
To produce energy for the cell
They are often called the powerhouse of the cell.
