Unit 1 - Cell Biology Flashcards
(28 cards)
What does the nucleus do
Control cell activities, contains DNA
What does the cytoplasm do
It’s where chemical reactions take place
What does the cell membrane do
Controls what goes in and out of a cell
What do the ribosomes do
Make proteins from amino acids (protein synthesis)
What do the mitochondria do
Release energy from respiration
What is the cell wall for
For strength/support, made from cellulose (eukaryotes only)
What does the vacuole contain
Cell sap
What do chloroplasts do
Contain chlorophyll for photosynthesis
What is a plasmid
Small ring of DNA
Name 3 specialised animal cells
Nerve, muscle, and sperm cells
Name 3 specialised plant cells
Xylem, phloem, root hair cells
How are nerve cells adapted for its function
Insulation - speeds up electrical impulses carried by the axon
How are sperm cells adapted for its function
Tail - so it can swim
Mitochondria - releases energy for swimming
How are xylems adapted for its function
No end plates or cytoplasm - to carry more water
Strengthened with lignin for support
How are phloems adapted for its function
End plates have pores - to allow dissolved substances through
Companion cells - provide energy for transporting sugars
How are root hair cells adapted for its function
Large surface area - to increase rate of absorption
Lots of mitochondria - to provide energy for active transport
Magnification formula
Magnification = Image size / Actual size
Where are stem cells found
Animals - bone marrow
Plants - meristem tissue
What is therapeutic cloning
- Get your patient’s body cell and a human egg cell
- Separate the nucleus from both cells
- Put the patient’s nucleus into the egg cell
This is used for medical treatment
What is diffusion
Particles moving from an area of high concentration to low concentration
Where does diffusion happen in the human body
- Oxygen diffuses from the blood into cells
- Carbon dioxide diffuses out of the cells into the blood
- Urea (waste product) diffuses out of cells
What factors affect diffusion
- Concentration gradient
- Temperature
- Surface area of the membrane (bigger surface area = faster diffusion)
What is active transport
Movement of particles from low to high concentration using energy (from respiration)
Where does active transport happen
- Sugar absorption in the small intestine
- Mineral ions in root hair cells
