Cell Specialisation + Organisation Flashcards
Why are specialised cells shaped and designed in a certain way?
To carry out their specific functions
How do cells become specialised?
Cells contain the genes to become specialised into different cells in an organism. However only some genes are expressed in any one cell. Different genes are expressed in each type of specialised cell.
Shape varies between specialised cells, what else differentiates between specialised cells? Give an example
The number of each organelle varies between specialised cells. For example, sperm cell may have many mitochondria, while a bone cell may have very few.
How are specialised cells organised?
Specialised cells are organised into tissues, then organs and then organ systems
What are tissues?
Tissues are a collection of similar cells that perform a specific function
What is an example of tissues? animal and plant example
- Epithelial cells.
They are found in animals, consist of sheets of cells and they line the surface of organs, often having protective or secretory functions there are many similar types like ciliated epithelium - Xylem.
They are found in plants, made up of a number of similar cell types. They are used to transport water and mineral ions throughout the plant, also providing mechanical support
What are organs?
A combination of tissues that are combined to perform a variety of functions, although they may have one main function
What is an example of an organ?
Muscles. They churn and mix the contents of the stomach
Epithelium. Protects the stomach wall and produces secretions
In plants, a leaf is an organ made of what tissues? These perform, what within the leaves?
Palisade mesophyll. made up of leaf palisade cells that carry out photosynthesis
Spongy mesophyll. adapted for gaseous diffusion
Epidermis that protects the leaf and allows for gaseous diffusion
Phloem that transports organic materials away from the leaf
Xylem which transports water and ions to the leaf
How can you determine what is an organ and what is tissue?
To determine whether something is an organ or tissue, you need to find out how many tissues construct this part. For example, capillaries are made up of one tissue so they are just tissue. Whereas muscle and epithelial are made up of multiple tissues, making them organs
What is an organ system?
An organ system is organs working together as a single unit, grouped together to perform a particular function more efficiently
What are some examples of organ systems and their functions?
- Digestive system. Digests and processes food. Made up of organs that include salivary glands, esophagus, stomach etc
- Respiratory system. Breathing and gas exchange. Made up of organs including the trachea, bronchi and lungs
- Circulatory system. Pumps and circulates blood. Made up of organs including the heart, arteries and veins
Out of the following, identify which are tissues or organs:
A. HEART
B. XYLEM
C. LUNGS
D. EPITHELIUM
A. HEART = organ
B. XYLEM = tissue
C. LUNGS = organ
D. EPITHELIUM = tissue
