B2 Flashcards
Where are palisade mesophyll cells found
Leaves and rectangular box-shaped cells that contain chloroplasts
Structure of palisade mesophyll cell and why has them features
Lots of chloroplasts that can spread out cytoplasm to maximise absorption of light for photosynthesis.
Cell surrounded by plasma membrane to protect the cell and to keep it rigid
Has a large vacuole ro maintain turgor presure
Root cell found and features why
Found in plants roots
Root hairs ro increase surface area and maximise movement of water and minerals from soil into root
Cells have thin cellulose walls and a vacuole containing cell sapphire with low water potential which encourages the movement of water in cell
Sperms cells found where
Male gametes in animals
Feature of sperms cell
Long tail called undolipodium to move to the egg
Contain lots of mitochondria for energy
Has acrosome which contains digestive enzyme which are released when touching the egg to fertilise it/deliver genetic info
50um long and 2.5um diameter
Flagella activated in vagina can swim 1 to 4mm per minute
Egg cells found where
Female gametes in animal
Features of egg cell
One of largest cells in body
Contains a nucleus which houses the genetic material
Zona pellucida is the outer membrane of cell to protect it
Corona radiata which Is 2/3 layers that supplies proteins needed to fertilise the egg
Egg is 0.1 diametr
Red blood cell features
Biconcave shape which increases surface area to volume ratio of erythrocyte
Flexible to squeeze through capillaries
Transports oxygen around the body
No nucleus to increase space of haemoglobin
White blood features
Multi-lobed nuclei which enables them to squeeze through small gaps when travelling site of infection
Cytoplasm hold lysosomes that contain enzymes to digest pathogens
Emphysema
Destruction damage of the alveoli
Walls
What happens to zonal pellucida after fertilised
Hardens/thickens/becomes impermeable
Which prevents more sperms cell entering the egg
Myelins role in conduction of nerve impulses in myelinated axons
Makes nerve impulses conduction faster and insulates axon
Action potential generated only at nodes
How many chromosomes does sperms have
Half
If efficiency of gas exchange is reduced what does this mean
Reduces elasticity
Increases diffusion path
Mucus build up
How does myelinated axons affect speed conduction
Conduction is faster due to myelin sheath which is made from shwann cells and insulates the axon
This prevents the loss of ions
The gaps between schwann cells are nodes of ranvier which is exposed axon membrane which is where action potential occurs
