Cells Flashcards
Define diffusion
higher concentration to lower concentration
Define Osmosis
from a higher H2O concentration to a lower H2O concentration
Define Endocytosis
movement into the cell
Define Exocytosis
movement out of the cell
Define Mitosis
cell division
Define Cytokineses
division of cytoplasm after the nucleus has divided
Define Centromere
button-like body holding sister chromatids together; also, the site of attachment to the mitotic spindle
Define Chromatin
the structures in the nucleus that carry the hereditary factors (genes)
Define Chromosome
barlike coiled chromatin
Define Hemolysis
the rupture of erythrocytes
How Does Movement of Materials across a Cell Membrane Occur?
- Passive transport
- Active
What is passive transport?
the movement from an area of high to low concentration
What type of energy is used to move molecules or ions in a passive transport?
Kinetic energy
What is Active transport?
movement of molecule from an area of low concentration
high concentration
What kind of energy is required in active transport?
ATP
What molecule makes of the basic framework of the plasma membrane?
phospholipid
What other molecules are found within the cell membrane?
proteins, glycolipids, cholesterol
Define facilitated diffusion
A carrier (transport protein in the membrane) is required for
diffusion of certain molecules across a membrane
Define Filtration
a high-pressure area to a lower-pressure area
What is an Isotonic solution?
equal amount of water inside and outside the cell
What is a hypotonic solution?
more movement of water into the cell
What is a hypertonic solution?
more water movement out of the cell
Define phagocytosis
cell eating
Define pinocytosis
Cell drinking
What is the Cytoskeleton?
Organelle that gives shape to the cell
What three filaments does the Cytoskeleton have?
- Microtubule
- Intermediate filaments
- Microfilaments
Why are microtubules important?
they form the mitotic spindle during mitosis
What is a ribosome?
Protein synthesis of products used within the cell
Where can ribosomes be found?
- Roaming free
- Rough endoplasmic reticulum
What is the rough endoplasmic reticulum?
Protein synthesis of products exported out of the cell or incorporated into the plasma membrane
What does the rough endoplasmic reticulum do?
transports of substancesm, such as proteins, within the cytoplasm
What is the smooth endoplasmic reticulum?
Lipid synthesis
What does the smooth endoplasmic reticulum do?
detox
What does the Golgi apparatus do?
Modifies, packages, secretes lipids and proteins
What does the Motichondria do?
Produce ATP
What does lysosomes do?
Digestion of carbohydrates, lipid, proteins, old cellular debris, wastes, and pathogens
What do Peroxisomes do?
Smaller than lysosomes and breakdown fatty acids and amino acids. Form hydrogen peroxide in the chemical reaction used to breakdown molecules
What do centrioles do?
Microtubule organizing center; responsible for mitotic spindle
formation
The Nucleus is composed of what four things?
- Nuclear membrane(envelope)
- Nucleoplasma
- Nucleolus
- Chromosomes
What is the nuclear membrane?
Composed of a double phospholipid bilayer
What is nucleoplasma?
fluid like substance within the nucleus
What is the nucleolus?
concentrated area of RNA and proteins
What are chromosomes?
DNA – genetic material,46 or 23 pairs
Does the cytoskeleton have a membrane?
No
Do Ribosomes have membranes?
No
Does the Rough Endoplasmic reticulum
have a membrane?
Yes
Does the Smooth Endoplasmic
reticulum have a membrane?
yes
Does the Golgi apparatus have a membrane?
Yes
Does the Mitochondria have a membrane?
Yes
Does a Lysosomes have a membrane?
Yes
Does a peroxisomes have a membrane?
Yes
Do centrioles have a membrane?
No
What is the shape of a mitochondria?
tiny, lozenge-like or sausage-shaped organelles
What are the shape of Ribosomes?
tiny, bilobed, dark bodies
What is the shape of the endoplasmic reticulum?
a system of fluid-filled tunnels (or canals) that coil and twist
What does a Golgi Apparatus look like?
a stack of flattened membranous sacs that are associated with swarms of tiny vesicles
What shape are Lysosomes?
membranous “bags” containing powerful digestive enzymes
What shape are Peroxisomes?
membranous sacs
What shape is the cytoskeleton?
An elaborate network of protein structures
What shape are centrioles?
rod-shaped bodies that lie at right angles to each other
What happens at the prophase?
As cell division begins, the chromatin threads coil and shorten so that the barlike chromosomes become visible under a microscope
What happens in the metaphase
the chromosomes line up at the metaphase plate (the center of the spindle midway between the centrioles) so that a straight line of chromosomes is seen.
What happens in the Anaphase?
he centromeres that have held the chromatids together split. The chromatids (now called chromosomes again) begin to move slowly apart, drawn toward opposite ends of the cell
What happens at telophase?
The chromosomes at opposite ends of the cell uncoil to become threadlike chromatin again. The spindle breaks down and disappears, a nuclear envelope forms around each chromatin mass, and nucleoli appear in each of the daughter nuclei.
What is cytokinesis?
Division of the cytoplasm
When does Cytokinesis begin and end?
Begines during late anaphase and ends during telophase
