2.1: Producing New Cells Flashcards
1
Q
What are diploid cells?
A
Cells with two matching sets of chromosomes
2
Q
What cells in the body are diploid?
A
All cells except sperm and egg cells
3
Q
Why do cells need to divide?
4
A
- Growth
- Repair of damaged tissues
- Replacement of damaged or dead tissues
- Maintajns the diploid chromosome compliment
4
Q
What is the process where cells divide?
A
Mitosis
5
Q
What are the steps of mitosis?
4
A
- Chromosomes shorten and thicken so that they become visible. Each chromosome is seen as a pair of chromatids
- The chromosomes line up along the equator of the cell, and the spindle fibres attach to them
- The chromosomes are pulled apart and the chromatids move to opposite ends of the cell, ready to divide
- The cell divides into two genetically identical daughter cells
6
Q
What are stem cells?
A
Unspecialised cells
7
Q
What are stem cells needed for?
A
Growth & Repair
8
Q
What can stem cells do?
2
A
- Self renew (to make more stem cells)
- Become specialised (to replace or renew existing specialised cells)
9
Q
What are the types of stem cells?
2
A
- Embryonic stem cells
- Tissue stem cells
10
Q
What are the features of embryonic stem cells?
2
A
- Found only in embryos
- Can specialise into any human cell
11
Q
What are the features of tissue stem cells?
2
A
- Only found in adults
- Can specialise into a few different cells
12
Q
How is the human body organised?
A
It is multicellular - made up of more than one cell, unlike bacteria which is unicellular
13
Q
What is the human body hierarchy?
A
Cells -> Tissues -> Organs -> Systems
