B2.1 Cells and Simple Cell Transport Flashcards
What is the function of the nucleus?
controls the activities of the cell
What is the function of the cytoplasm?
Where most chemical reactions take place
What is the function of the cell membrane?
controls the passage of substances into and out of the cell
What is the function of the mitochondria?
where most of the energy is released in respiration
What is the function of ribosomes?
where protein synthesis occurs- where proteins are made. Mitochondria provides the energy for the process
What extra parts do plant and algae cells have?
cell wall, chloroplasts, permanent vacuole
What is the function of chloroplasts?
absorb light energy to make food by photosynthesis
What is the function of the cell wall?
made of cellulose, strengthens the cell
What is the permanent vacuole filled with?
Cell sap
Describe the structure of a bacterial cell
cytoplasm, cell membrane, cell wall, genes are not in a distinct nucleus
Describe the structure of a yeast cell
single celled organism, nucleus, cytoplasm, cell membrane, cell wall
Why may cells be specialised?
to carry out a particular function
How do dissolved substances move in and out of cells?
by DIFFUSION
What is diffusion?
The spreading out of particles of gas or any substance in solution, resulting in a net movement from a region where they are of a higher concentration to a region with a lower concentration.
The greater the difference in concentration, the faster the rate of diffusion.
How does oxygen required for photosynthesis pass through cell membranes?
by DIFFUSION
How are palisade leaf cells adapted for photosynthesis?
Packed with lots of chloroplasts at the top of the cell.
Tall shape- larger surface area exposed down the side for absorbing CO2
Describe how guard cells are adapted to open and close stomata in leaves
Sensitive to light -close at night to save water
special kidney shape which opens and closes stomata
Describe how red blood cells are adapted to carry oxygen
concave shape- larger surface area for absorbing oxygen and allows them to pass through smoothly through capillaries.
no nucleus- more room for haemoglobin- pigment that absorbs oxygen
Describe how sperm cells are specialised for reproduction
long tail and streamlined head to help it swim fast
lots of mitochondria in cell to provide it with energy
carries enzymes in the head to digest through the egg cell membrane
Describe how egg cells are specialised for reproduction
contains huge food reserves to feed the embryo
membrane changes structure to stop any other getting in after first sperm to make sure offspring gets the right amount of DNA
What do most human and animal cells have?
nucleus, cytoplasm, cell membrane, mitochondria, ribosomes
Explain how oxygen passes from the blood to the mitochondria in cells
by diffusion
from high to low concentration
through cell membranes
Describe how the ribosomes and mitochondria help a cell to make enzymes
ribosomes make proteins
using amino acids
mitochondria provides the energy for this process
