T1 - Specialised and stem cells Flashcards
What is a specialised cell?
Specialised cells are cells that have a specific role in the body and have a specific shape or structure in order to help them fulfill these roles.
What is differentiation?
Differentiation is the process in which a cell changes to become specialised.
What is a nerve cell?
Explain how a nerve cell is adapted to it’s role.
A nerve cell carries electrical signals from one part of the body to another.
The cells are long to cover more distance.
They have branched connections at their ends to connect to other nerve cells and form a network throughout the body.
What is a sperm cell?
Explain how a sperm cell is adapted to it’s role.
A sperm cell delivers genetic material to an egg in order to fertilise it.
It has a flagellum and streamlined head to help it to swim to the egg.
There are lot’s of mitochondria in the cell to provide the energy needed.
It carries enzymes in it’s head to digest through the egg cell membrane.
What is a muscle cell?
Explain how a muscle cell is adapted to it’s role.
The function of a muscle cell is to contract quickly.
The cells are long so that they have space to contract.
They contain lot’s of mitochondria to generate the energy needed for contraction.
What is a root hair cell?
Explain how a root hair cell is adapted to it’s role.
Root hair cells are cells on the surface of plant roots which grow into long “hairs” that stick out into the soil.
This gives the plant a big surface area for absorbing water and mineral ions from the soil.
What is a xylem cell?
Explain how a xylem cell is adapted to it’s role.
A xylem cell transports water and minerals from the roots up the plant stem and into the leaves.
Xylem cells are hollow in the centre so that things can flow through them.
What is a phloem cell?
Explain how a phloem cell is adapted to it’s role.
Phloem cells move food substances that the plant has produced by photosynthesis to where they are needed for processes.
Phloem cells have very few subcellular structures so that things can flow through them.
What are stem cells?
Stem cells are cells that have not undergone differentiation. They can differentiate into different types of cells depending on what instructions they are given. They divide by mitosis to form more cells.
What is the difference between embryonic stem cells and adult stem cells?
Embryonic stem cells can differentiate into any type of cell however adult stem cells can only turn into certain cells such as platelets, red blood cells and white blood cells.
Where are stem cells found?
Embryonic stem cells - Embryos
Adult stem cells - Bone marrow
Plant stem cells - Meristems
What are the negatives of embryonic stem cells?
Embryonic stem cells have a limited supply, some peoples bodies reject them.
There are ethical issues around embryonic stem cells as embryos are a potential human life.
What are plant stem cells?
Plant stem cells are found in the meristems (parts of the plant where growth occurs). Throughout the plant’s entire life cells in the meristem tissues can differentiate into any type of plant cell.
They can be used to produce clones of whole plants quickly and cheaply, and grow more plants of rare species.
