Cells and Tissues Flashcards
(73 cards)
What are the four types of tissue?
Epithelial
Nervous
Muscle
Connective
What is the cell membrane? What is it’s function?
Surrounds the cell, separating the external environment from the cytoplasm
FUNCTION: Controls what enters and leaves the cell.
What is the structure of a cell membrane?
Phosopholipid bilayer.
Is a cell membrane fully or partially permeable?
It is partially permeable.
Has protein molecules embedded in it that allow transport of substances in and out of cell.
What is the centriole?
A small structure.
Normally located close to nuclear membrane.
Involved in cell division.
What is a lysosome?
Formed from the ends of Golgi apparatus ( body.)
Contains digestive enzymes, collectively called lysozyme.
FUNCTION: lysozyme is used by phagocytes to digest bacteria and is responsible for autolysis of cells after their death.
Also found in tears and helps protect the eye against bacterial infection.
What is the cytoplasm?
A gel like substance tat surrounds all organelles outside the nucleus/
Also contains enzymes that speed up (catalyse) biochemical reactions in the cell
What is the nucleus?
Contains the genetic material ( DNA).
DNA is organised into genes on chromosomes that controls protein synthesis.
What does DNA stand for?
deoxyribonucleic acid
What is the structure and function of the Rough Endoplasmic reticulum?
System of tubes and sacs studded with ribosomes on the external surface.
Function: ribosomes are involved in the manufacture of membrane bound proteins.
What is the nucleolus?
Can there be more than one per cell?
A round structure in the nucleus where ribosomes are produced.
Also contains large amounts of DNA and RNA ( ribonucleic acid).
Some nuclei have more than one nucleolus.
What is the structure and function of the smooth endoplasmic reticulum?
Structure: system of tubes and sacs
Function: synthesises lipids
Does the nucleus have a membrane?
Yes.
It is a barrier separating the nuclear constents from the cytoplasm.
There are numerous pores in the nuclear membrane, which facilitate and regulate the exchange of materials between the nucleus and the cytoplasm.
What are ribosomes and where are they found?
They are responsible for manufacturing proteins.
Some are unattached in the cytoplasm but they are more commonly attached to the surface of rough e.r.
What is a vacoule?
A small organelle with a minor function of facilitating transport in and out of cells (by endocytosis and exocytosis)
What is the Golgi apparatus appearance and function?
Flattened sacs.
Function: Package proteins and carbohydrates into vesicles for export from the cell.
What is the mitochondian ( plural- mitochondria)
Provides energy in the form of ATP
ATP provides energy for muscle contraction, active transport and to build large molecules.
Are the membranes of cell organelles fully permeable?
No
These are partially permeable also.
What is the structure and function of the cytoskeleton?
A complex lattice structure of protein microtubules.
FUNCTION: Maintain cell shape.
What are the four classes of membrane in the human body?
1) Mucous
2) Cutaneous
3) Serous
4) Synovial
Membranes are sheet like structure found throughout the body that perform specific functions.
What is the location and structure of mucous membranes?
Line openings to the body- such as the respiratory, digestive, urinary and reproductive tracts.
Cells produce lubricating mucus.
What does cutaenous membrane line?
The skin
Discuss the structure and function of serous membranes?
Produce serous fluid which reduces friction between tissues and organs.
Has two layers- parietal and visceral.
Parietal- line the walls of cavities in which the organ resides.
Visceral layer- wraps around organs.
Describe the location and function of synovial membrane?
Found in the spaces between joints and produces synovial fluid which reduces friction between joints during movement.
