Chapter 3- Cells Flashcards
1
Q
Cell Theory
A
Cells are the building blocks that make up all living organisms
2
Q
What makes up the cell structure
A
Cell membrane Cytoplasm Organelles Cytosol Cytoskeleton Inclusions .
3
Q
Parts of a cell
A
Cytoplasm Centrioles Endoplasmic reticulum Ribosomes Cytoskeleton Inclusions Lysosomes Nucleus Mitochondria Golgi body Cell membrane
4
Q
Cytoplasm
A
- Thick fluid within cell membrane
- structures of cell are suspended in it
- cytosol is the liquid part of cytoplasm: 75-90% water
5
Q
Centrioles
A
- Pair of cylindric structures
- located near the nucleus
- involved in cell reproduction
6
Q
Endoplasmic reticulum (ER)
A
- pairs of parallel membranes that extend through cytoplasm
- connect cell membrane with nuclear membrane
- provides surface for chemical reactions
- channels between membranes: are used for storage or transport of material
- rough ER- ribosomes attached
- smooth ER- no ribosomes attached
7
Q
Ribosomes
A
- small and spherical
- some free in cytoplasm
- some attached to membranes
- at ribosomes: amino acids are joined together to make proteins
8
Q
Cytoskelton
A
- consists of microfilaments and microtubules: give shell its shape
- assists with movement of materials, organelles or the whole cell
9
Q
Inclusions
A
- not part of cell structure
- found in cytoplasm
(Eg. Haemoglobin in red blood cells)
10
Q
Lysosomes
A
- small spheres bounded by a membrane
- formed in the Golgi body
- contain digestive enzymes that break down large molecules
- when particles are taken into a cell they form vesicles in the cytoplasm and then lysosomes join to these vesicles an breaks down material inside of them
- also digest worn out organelles
11
Q
Nucleas
A
- spherical
- contains genetic material DNA
- separated from cytoplasm by nuclear membrane
- has a double membrane with nuclear pores
- large molecules pass through nuclear pores
- an area in nucleus is called nucleolus
- nucleolus is composed mainly of RNA
- nucleolus plays a part in manufacture of proteins
- DNA and nucleolus is suspended in jelly-like nucleoplasm
- largest organelle in the cell
12
Q
Mitochondria
A
- spherical or elongated structures spread through cytoplasm (sausage shaped)
- has a double membrane: outer membrane is smooth and the inner one is folded
- release energy for the cell through cellular respiration
- folding of inner membrane provides large surface area where chemical reactions can take place
- because of the reactions mitochondria make energy available for cells activities
13
Q
Golgi Body
A
- flattened membranous bags stacked on top of each other
- modify proteins and package them in vesicles for secretion
- vesicles are pinched off from the edges of the membrane
- positioned near nucleus
- proteins produced at ribosomes pass through endoplasmic reticulum channels to Golgi body
14
Q
Cell membrane
A
- outer boundary of the cell
- separates from neighbouring cells and external environment
- made up of a double layer of lipid molecules and proteins
- determines which substances get into and out of the cell
15
Q
Cytosol
A
- liquid part of cytoplasm
- 76-90% water with complex mixtures of dissolved substances
- salt and carbohydrates are dissolved in cytosol
- substances like proteins and fats do not dissolve but suspend in the fluid
16
Q
Organelles
A
- structure within the cell
- many types of different organelles
- formed in cells internal membrane
17
Q
DNA
A
- located in the nucleus
- when cell isn’t diving: DNA is in long threads
- when cell is dividing: thread the thicken and coil to form chromosomes
- contains information that determines type of protein a cell can make
- ## the nucleus with its DNA controls the structure and unction of a cell
18
Q
Cilia
A
- short and numerous projections resembling tiny hairs
- move substances over the cell or move the whole cell
- occurs in lining of the windpipe: where they move mucous and trapped particles towards the throat
19
Q
Flagella
A
- projections that can move a whole cell or substances over a cell
- long and few projections
- occurs in only one type of cell which is the sperm cell: enables the sperm to swim to the egg
20
Q
Why are cells so small
A
- more surface area which means more chemical reactions can take place
- surface area to volume ratio increases as the cells size decreases
