B4 - Organising Animals and Plants Flashcards
what is an aveoli
- have a large surface area for fast diffusion
- close blood supply to create a short diffusion distance
- cell wall is 1 cell thick
- has a good blood supply which maintains the concentration gradient
what are homeostatis
the process by which an organism tend to maintain stability while adjusting to conditions for survival
what is the control system
cells called receptors that detect stimuli, a coordination centre that recieves and processes information from receptors
what is the nervous system
- allows humans to respond to changes in the enviroment
- the information travels as electrical impulses
- the muscle responds to impulses by contracting
what is transpiration
the loss of water from a leaf by evaporation through the stomata
what is the transpiration stream
- water is absorbed by roots via osmosis
- up the xylem
- to the leaf
- evaporates through the stomata
what is the xylem
cells transport water and minerals up the stem from the roots and leaves
what is the pholem
cells transport glucose produced in the leaves up and down the stem to grow and storage tissues
what is translication
the movement of dissolved glucose up and down the pholem to grow parts for respiration and for storage
what is paliside mesophyll
- where photosynthesis occurs
- known as the leaf cells
what is the waxy cuticle
- reduces water loss from the leaf
what is the epidermal
contain no chloroplasts
what are guard cells
they control gas diffusion by regulating stomatal pores
what is the stomata
- allows carbon dioxide and oxygen in and out of the cell
what is the spongy mesophyll
has air spaces for lots of diffusion
in a plant what is the purpose of a leaf
to carry out photosynthesis
in a plant what is the purpose of the roots
to absorb water and nutreints from the soil, it is also used to anker the plant into the soil