Lab Chp. 2: Cell Structure and Divison Flashcards
the basic, structural and functional living unit of any body
cell
A cell consists of:
- A boundary (plasma membrane)
- A cell body
- A set of genes
What are the three major regions of a cell?
- plasma membrane
- Cell Body
- Genes
a “fluid” phospholipid bilayer is part of the
plasma membrane (e.g., cholesterol)
Regulates the type of molecules that enter and exit the cell
plasma membrane
What part of the cell helps communicate with other cells?
Plasma membrane
The cell body is filled mostly with ______
cytoplasm
A cell body is made up of:
- cytosol
2. organelles
part of the cytoplasm that is not contained in membrane bound organelles
cytosol
Where are genes found?
In the nucleus
Genes control:
- cellular structure
- most cellular activities
Tiny structures that perform specialized tasks
organelles
______ are organelles that are not membrane bound
ribosomes
Cytosol is about _____% of the total cell volume
55%
Cytosol is about _______% water.
75-90%
For cellular grown, maintenance, and reproduction
organelles
What are the two components of cytoplasm?
- cytosol
- organelles
A network of different protein filaments that extend out into the cytosol
cytoskeleton
Provides a structural framework
cytoskeleton
- Found near the nucleus
- organizes microtubules
Centrosome
- is 9 clusters of 3 tubules
- Aid in mitosis
- Form basis of cilia and flagella
Centrioles
Move things past the cell but DO NOT move the cell
cilia
Move the cell
flagella
What are the only cells with flagella in the human body?
Sperm cells
Site of protein synthesis
Ribosomes
- made up of two subunits
- some are free and others are membrane-bound
*Attach to E.R.
- Synthesizes steroids, fatty acids, phospholipids
- Detoxify certain drugs through enzymes
- stores calcium needed for muscle contraction
Smooth E.R.
Made up of cisterns
Endoplasmic Reticulum
- studded with ribosomes
- synthesizes proteins (e.g., insulin)
Rough E.R.
Refines and packages the products of the Rough and Smooth E.R.
The Golgi Apparatus
Products of the Golgi Apparatus are packaged in ________ _________
transport vesticles
Membrane bound sphere
vesticles
vesicles that send their materials to areas outside of the cell where they are made
secretory vesticles
- Contain digestive enzymes to break down food
- break down old, worn-out organelles
Lysosomes
Use oxygen to break down waste
Peroxisomes
(When they use oxygen to break down waste, it forms peroxide)
*Contains catalase enzymes to break down peroxide
Mitochondria
- “Powerhouse of the cell”
- Site of ATP synthesis
- Have their own DNA
- contains cristae (inner membrane)
What are good for tracing maternal DNA
mitochonria
Which has more surface area, the inner membrane or the outer membrane of the mitochondria?
The inner membrane
Nucleolus
Site of RNA formation
Contains DNA
Nucleus
Can DNA escape through the nuclear envelope?
No, but RNA can
Nucleus
- Holds the genetic blueprint (DNA)
- Site where information in DNA is copied into RNA
- Where protein formation is initiated
Writing DNA into RNA
Transcription
How does RNA differ from DNA?
- Sugar is ribose (DNA is doxiribose)
- has uracil instead of thymine
- is single stranded
What is the major goal of mitosis?
Major Goal: to distribute a copy of each chromatid into each daughter cell
How many phases does Mitosis have?
4
Prophase
Duplicated chromosomes are visible. Centrosomes begin moving apart; nuclear envelope is fragmenting and nucleolus will disappear.
Metaphase
Chromosomes (each containing two sister chromatids) are at the metaphase plate (center of fully formed spindle)
Anaphase
Daughter chromosomes are moving towards the poles of the spindle
Telophase
Daughter cells are forming as nuclear envelopes and nucleoli appear. Chromosomes will become indistinct chromatin
Cytokinesis beings with what Mitotic phase?
Anaphase
*ends after telophase
Cell division is _______ to the mitotic spindles.
perpendicular
Cell division starts with the ______ ______ pinching the animal cell into two.
contractile ring
When cells divide in telophase, a ____ ______ becomes apparent.
Cleavage furrow
List the general characteristics of epithelial tissue
- cover exterior surface of body and internal organs
- line walls of body cavities and interior of hollow organs
- tissue has free surface
- tissue anchored by a basement membrane at bottom
- cells readily divide by mitosis
flat
squamous
cude-shaped, rounded corners
cuboidal
elongated (tall/thin)
columnar
one layer
simple
more than one layer
stratified
looks stratified, but really just one layer
pseudostratified
Simple Squamous Epithelium
- single layer of flat cells
- substances pass through easily
- line air sacs of lungs, blood vessels, and lymphatic vessels
simple cuboidal epithelium
- single layer of cube-shaped cells, rounded corners
- form kidney tubules and ducts of some glands
simple columnar epithelium
- single layer of elongated (tall/thin) cells
- nuclei near the basement membrane at same level
- often have goblet cells for secretion of mucus
- sometimes possess microvilli
- line stomach and intestines
stratified squamous epithelium
- Many cell layers
- top cells are flat, but lower cells are rounded
- lines mouth and esophagus
- forms outer layer of skin where top cells become keritanized (tough, waterproof)
simple squamous epithelium
line air sacs of lungs, blood vessels, and lymphatic vessels
simple cuboidal epithelium
form kidney tubules and ducts of some glands
simple columnar epithelium
line stomach and intestines
pseudostratified columnar epithelium
- single layer of elongated (tall/thin) cells
- nuclei at two or more levels
- appear stratified, but really have a single layer
- often have cilia (movement) and goblet cells (mucus)
- line respiratory passages
stratified squamous epithelium
forms outer layer of skin where top cells become keritanized (tough, waterproof)
stratified cuboidal epithelium
sweat glands, salivary glands, and pancreas
stratified columnar epithelium
found in male urethra and parts of the pharynx
What is the function of the microvilli?
They increase the surface area of the cell and aid in absorption
What are the three main parts of any cell?
- Plasma Membrane
- Cell Body
- Genes
Discuss the composition and function of cytoplasm
a. Cytosol- about 55% of total cell volume
b. Organelles- for cellular growth, maintenance, and reproduction
Discuss the composition and function of cytoskeleton
a. A network of different protein filaments that extend out into the cytosol
b. Provides a structural framework
Where is protein formation initiated?
Nucleus
Mitosis
Division of a somatic cell nucleus during cell divison
Cytokinesis
Division of the cytoplasm during the cell cycle
Contractile Ring
contraction which causes the plasma membrane to pinch inward and the cell to divide (pinching the animal cell into two)
cleavage furrow
a groove in the plasma membrane between daughter nuclei