B2 part 1 Flashcards
(31 cards)
What happens to the number of cells as you grow in your body
They will increase because the larger the organism, the more cells it will contain
What is the function of the nucleus?
It contains all chromosomes made of DNA. The nucleus controls all the activities of the cell and how it develops
What is the function of ribosomes
Protein synthesis
What is the function of the permanent vacuole
Fluid filled cavity containing cell sap. Used for reinforcement of cell
Why are plant cells not as flexible as animal cells?
Plant cells have a rigid cell wall whereas animal cells have a flexible membrane
What are the differences between a bacterial and a fungal cell?4⃣
- Fungal cells are larger,
- Fungal cells are made of a chemical called chitin,
- Fungal cells include a vacuole,
- Bacterial cells have a loop of DNA but fungal have a nucleus
Explain why biologists discovered bacterial cells later than plant cells
Plant cells only need a magnification of x500 but bacterial cells need a stronger, more complex electron microscope of x15 000
What are specialised cells
Cells that carry out a particular job or function
What is a red blood cells function and how is it adapted to do this?
The haemoglobin in the rbc binds to oxygen and transports it around the body to other cells. It had a large SA but is small so fits into narrow vessels
How is a sperm cell adapted to fit it’s function
It has a long tail full of mitochondria for swimming fast to the egg cell. It’s head is full of DNA which combines with the DNA in the egg cell
Explain how a large surface area helps the root hair cell to absorb water and minerals
Improves its ability as there is more surface area so the particles diffuse across quicker.
State three factors that affect the rate of diffusion
- distance
- concentration gradient
- surface area
What are tissues
A group of similar cells working together
What is an organ
Organs are tissues that are made of several types of tissue
Name two organs that produce digestive juices
- Pancreas
- salivary gland
What is yeast
Single cell organism
Type of fungal cell
Made of chemical called chitin
What is diffusion
Movement of particles from an area of high concentration to low concentration
What is a solute
Particles in a solution
What is a solvent
Particles dissolved in a liquid
How can salutes move in and out of a cell
By diffusion
What does a muscular tissue do
It contracts to perform movement
What does a glandular tissue do
Produces enzymes and hormones
Epitheral tissue
Covers part of body eg stomach
What do glands do in the digestive system
Produce digestive juices
