Tissues and organs Flashcards
3 types of animal tissue and their purposes?
Muscular - contracts for movement; glandular - secrete substanes; epithelial - covers and protects
Hierarchy of organisms?
Cell - tissue - organ - organ system - organism
3 types of plant tissue and their purposes?
Epidermal - cover and protect; mesophyll - photosynthesis; xylem and phloem - transport water and mineral ions
Define tissue
A group of cells with similar structures and functions working together
Define organ
Several tissues working together
Define differentiation
When cells during the development of a multicellular organism become specialised to carry out specific jobs
What roles do each of the tissue types complete in the stomach?
Muscular - churns food and juices together; glandular - secretes enzymes and acids (digestive juices) that break down food; epithelial - covers inside and out
What about the glandular tissue in the stomach makes it particularly effective?
It is folded so it has a large surface area from which to secrete juices
What are the functions of the pancreas?
To make hormones that control blood sugar; to make some digestive enzymes
Three examples of exchange taking place within organs?
Gases in the lungs; digested food from small intestine to blood; dissolved substances from blood to kidney tubules and back
Why do many organs have a good blood supply?
To maintain the steep concentration gradient to speed up diffusion
Where in the human body is food mainly digested?
Stomach and small intestine
Function of small intestine?
Soluble food molecules absorbed into blood
Function of large intestine?
Water absorbed from undigested food to form faeces
Function of xylem tissue?
To transport water and minerals around the plant
