chp 3 Flashcards
cell membrane
outer boundary of cell, made up of a double layer of lips (phospholipid bi layer)
separates the cell from neighbouring cells and external environment. Determines which substances get into or out of the cell
cytoplasm
within the cell membrane. Thick fluid within cell membrane and all structures suspended in it it is more jelly like than cytoskeleton.
cytoplasm is responsible for giving a cell its shape. It helps to fill out the cell and keeps organelles in their place
nucleus
Central region of the cell. Separated from cytoplasm by a nuclear membrane. DNA and nucleolus are suspended in nuclearplasm.
contains genetic information, 23 pairs of chromosomes. Nuclear membrane has gaps known as pores which large molecules can pass through. Nucleolus makes ribosomal RNA which makes ribosomes
ribosomes
free inside cytoplasm or bonded to endoplasmic reticulum. Very large spherical organelles found in all living cells.
Amino acids are joined together at the ribosomes to make proteins, does RNA translation. Found on their own inside a possum or attached to endoplasmic reticulum
endoplasmic reticulum
attached to the nucleus. Pairs of parallel membranes extending through cytoplasm and connecting cell membrane to nuclear membrane, some have ribosomes attached. Provides the surface in which chemical reactions can occur. Channels between paired membranes are used for storage or transport of materials. Rough ER is where proteins are made
golgi body
Three in cytoplasm. Flattened membrane bag stacked on top of each other. They modify proteins and package them in vesicles for secretion from the cell. Vescicles are pinched off from the edges of membranes.
lysosomes
small spheres that contain enzymes able to break down proteins, lipids, nuclear acids and some carbohydrates. They break down proteins and other materials that are taken into the cell or breakdown worn out organelles. Has digestive enzymes. If it explodes, enzymes spread out and cell dies
mitochondria
spiracle elongated structures spread through cytoplasm. Have a double membrane and its own DNA. Folded membrane inside a membrane.
release energy for the cell through the process of respiration. Powerhouse of the cell, provide energy in the form of ATP
centrioles
near the nucleus. Pair of cylindrical structures perpendicular to each other.
involved in the reproduction of the cell they form spindle fibres
cilia/flagella
on the surface of the cell. Tiny hairs called cilia, if it is longer and fewer it is called flagella
they move mucus and trapped particles (cilia in windpipe)
flagella in sperm cell helps it swim
cytoskeleton
free in cytoplasm along the cell membrane
they are a framework of protein fibres that give the cell its shape and assists in cell movement. Made of microtubules and microfilaments
keep organelles in place and/or move them around the cell. Support them. Also moves materials and the whole-cell
inclusions
Chemical substances are not a part of the cell structure it is in the cell as granules or droplets
they can help and pigments, store nutrients,secretary products and pigment granules
vacuole
distributed through cells cytoplasm
Storage bubbles found in the cell
Store food or any variety of nutrients are cell might need to survive
why are cells so small
there is a limit to how big a cell can be.
A small cell will have a larger surface area to volume ratio then a large cell.
apple analogy
cells have to be microscopic to function effectively.
A large cell could not support itself because it would not have enough surface to absorb the nutrients required, and remove the wastes produced by its large volume
