Cell structure and transport Flashcards
Oxygen will diffuse into the cell above, why? (1)
Because there is a high to low oxygen concentration
For what process do cells use oxygen
Respiration
How are these muscle cells adapted to release a lot of energy (2)
They contain many mitochondria for respiration
Name the structure in the animal cell that contains genetic material
Nucleus
What is osmosis
Osmosis is the movement of water particles
from a dilute to a more concentrated solution
through a semi permeable membrane.
Explain how this plant root is adapted to absorb water (3)
There are many hairs
which gives a larger surface area
so there is more osmosis of water into the root
Cells use respiration to release
Energy
Describe function of mitochondria and explain why they are arranged around a filament near the tail of the sperm (3)
Energy released
near site of movement
so energy is available quickly as there is efficient arrangement
Explain the significance of the Nucleus in determining the characteristics of the offspring (2)
Contains genes which contribute to half the genes to the offspring
Name the process by which gases move in and out of the cell
Diffusion
Describe the functions of muscle cells in walls of the stomach
They contract
to churn food
Function of mitochondria (2)
Transfer energy for use by aerobic respiration
Function of ribosome
To make proteins
Why can’t ribosomes be seen through a light microscope?
Ribosomes are too small
Why do epithelial cells have a faster rate of diffusion? (1)
It has a larger surface area
Name enzyme produced by salivary glands
Carbhohydrase
Define Hypertonic
Solution is more concentrated than the cell
Define Hypotonic
Solution is less concentrated than the cell
Word used to describe plant cells placed in a hypotonic solution
Turgid
Word used to describe plant cells placed in a hypertonic solution(1)
Plasmolysed
Red blood cells are placed in a hypotonic solution. Predict what will happen (4)
Water enters the cell by osmosis
the cells burst
as animal cells have no cell wall
and the cell wall prevents bursting
The flagellum helps the cell to move through water. Scientists think that the flagellum and the light-sensitive spot work together to increase photosynthesis.
Suggest how this might happen. (2)
Light sensitive spot detects light and tells flagellum to move towards light
Multicellular organisms often have complex structures, such as lungs, for gas exchange.
Explain why single-celled organisms, like algae, do not need complex structures for gas exchange. (3) (4 points needed)
Cell has a larger surface area to volume ratio
short diffusion distance
diffusion by cell membrane is sufficient
flow of water maintains concentration gradient
Name one food molecule absorbed into epithelial cells by active transport
Glucose
Why is it necessary to absorb some food molecules by active transport? (1)
Active transport is against a concentration gradient
Suggest why epithelial cells have many mitochondria (2)
Active transport is requires energy from respiration
Name one substance that plants absorb by active transport
Minerals
Diffusion is an important process in animals and plants.
The movement of many substances into and out of cells occurs by diffusion.
Describe why diffusion is important to animals and plants.
In your answer you should refer to:
• animals
• plants
• examples of the diffusion of named substances.
Diffusion is important to take in substances for use in cell processes
and removes waste products from cell processes
Animal use diffusion for gas exchange to take in O2 in and let CO2 out. This happens down a concentration gradient in the lungs.
Plants use diffusion for gas exchange to take in CO2 and let O2 out. This happens down a concentration gradient on the stomata
Define down a concentration gradient
High to low concentration
Define against a concentration gradient
Low to high concentration
. In fish and chip shops, potatoes are cut into chips several hours before they are cooked.
The mass of water in the chips must be kept constant during this time.
To keep the water in the chips constant, the chips are kept in sodium chloride solution
Describe how you would use the apparatus and materials shown in the drawing to find the concentration of sodium chloride in which to keep the chips so that the mass of water in the chips remains constant. (6)
You should include:
• the measurements you would make
• how you would make the investigation a fair test.
use of scalpel to cut chips to same dimensions
use of range of sodium chloride concentrations
use of forceps to transfer chips
use of balance to measure mass of chips before immersion, record the results
use of balance to measure mass of chips after immersion, record the results
To make it a fair test make sure that the chips left in solutions for same length of time
