Revision Checklist Flashcards
What is cell differentiation?
The process by which cells become specialized in structure and function through gene expression.
Cell differentiation allows for the diversity of cell types in multicellular organisms despite all cells being genetically identical.
How are all cells in a multicellular organism genetically identical?
All cells originate from a single fertilized egg cell, undergoing mitosis to produce genetically identical cells.
This genetic identity is maintained through cell division.
What is the hierarchical structural organisation?
Cells → Tissues → Organs → Systems.
This hierarchy illustrates how cells group to form tissues, which then form organs, and finally systems.
Give an example of how cells are organized into tissues in plants.
-In plants, parenchyma cells form the tissue that makes up leaves and stems.
-Vascular tissue is made up of specialised cells called xylem and phloem.
Xylem: transports water and minerals throughout the leaf
Phloem: transports glucose produced by photosynthesis
Tissues can be specialized for functions like photosynthesis or storage.
Describe the relationship between structure and function in cells.
The structure of a cell is directly related to its function, such as the shape of neurons facilitating signal transmission.
This principle applies to tissues and organs as well.
What is organ system interdependence?
The concept that different organ systems work together to ensure the survival of the organism.
For example, the circulatory and respiratory systems work together to supply oxygen to the body.
How do lifestyle choices affect the functioning of organs and systems?
Lifestyle choices like diet and exercise can influence organ health and efficiency.
Poor lifestyle choices may lead to diseases affecting organ systems.
What are examples of material exchange in multicellular organisms?
Gas exchange in the lungs, nutrient absorption in the intestines.
These processes are vital for maintaining homeostasis.
What are the requirements for effective exchange surfaces?
Exchange surfaces must be thin, moist, and have a large surface area.
A rich blood supply also enhances material exchange.
How does the respiratory system facilitate gas exchange?
The structure of alveoli maximizes surface area for gas diffusion between internal and external environments.
Alveoli are surrounded by capillaries to facilitate this exchange.
What is the difference between diffusion and active transport?
Diffusion is the passive movement of molecules from high to low concentration, while active transport requires energy to move substances against a concentration gradient.
Active transport is essential for nutrient uptake in cells.
Describe the structure of a leaf from the top to the bottom.
- Waxy cuticle
- Upper epidermis
- Palisade mesophyll
- Vascular tissues (xylem and phloem)
- Spongy mesophyll
- Lower epidermis
- Stomata (and guard cells)
- Waxy cuticle
This structure allows for efficient gas exchange and photosynthesis.
How do gases move into and out of plants?
Gases move through stomata via diffusion and osmosis.
Carbon dioxide enters the leaf for photosynthesis.
Oxygen, produced during photosynthesis, exits the leaf.
Stomata open and close to regulate gas exchange and water loss.
What is transpiration?
The process of water vapor loss from plant leaves through open stomata.
Transpiration helps in nutrient transport and temperature regulation.
What is the structure and function of the circulatory system?
The circulatory system consists of the heart, blood vessels, and blood, supporting the transport and exchange of materials throughout the body.
It plays a crucial role in delivering oxygen and nutrients to tissues.
What does it mean that the lymphatic system is closely connected to the circulatory system?
Extracellular fluid that does not return to the capillaries at the venule end is picked up by lympth vessels.
The lympathic system returns protein and excess ECF to the circulatory system near the heart.
Compare the role of blood capillaries and lymph capillaries.
Blood capillaries exchange nutrients and gases with tissues, while lymph capillaries absorb excess fluid and waste from tissues.
Both systems are essential for maintaining fluid balance.
What is the excretory system in animals?
The system responsible for removing waste products from the body, primarily through the kidneys.
It helps maintain homeostasis and fluid balance.
Describe the structure and function of nephrons.
Nephrons are the functional units of the kidney, responsible for filtration and reabsorption of water and solutes.
They play a key role in urine formation.
What is osmoregulation?
The process of maintaining the balance of water and solutes in the body.
It is crucial for cellular function and overall homeostasis.
What is the importance of the digestive system?
The digestive system breaks down food and absorbs nutrients necessary for survival.
It plays a critical role in energy supply and metabolic processes.
How does the structure of digestive organs relate to their function?
Organs like the stomach and intestines are specialized for digestion and nutrient absorption due to their structure.
For example, the stomach has a muscular wall for churning food.
Describe the structure and function of villi.
Villi are small, finger-like projections in the small intestine that increase surface area for nutrient absorption.
Their structure allows for efficient uptake of nutrients into the bloodstream.
