LESSON 4: CELL CYCLE Flashcards
● Phospholipid bilayer
● Hydrophilic head and hydrophobic tail in two layers
○ The outer portion is the hydrophobic region of
the cell membrane
● Based on the fluid-mosaic model, the lipid bilayer is the
core of the membrane
● Contains cholesterol, cardiolipin, sphingomyelin
● Contains carbohydrates known as oligosaccharides and
membrane proteins
Cell membrane
Membrane Proteins:
■ Integral Proteins
■ Lipid-anchored Proteins
■ Peripheral Proteins
Cell membrane
● Several ________ are found in the cytoplasm
● The presence and abundance of the different __________
varies between different tissues and different organisms
● Suspended in a fluid-filled region called the cytosol
Organelles
● Non-membrane bound organelles that are responsible for the synthesis of protein
● Made up of small sub-unit (40 S) and large sub-unit (60 S)
● Also contains protein and rRNA which are synthesized in the nucleolus
Ribosomes
● May be attached to the endoplasmic reticulum specifically called _______ Endoplasmic Reticulum or may be free floating in the cytoplasm
● _________ can also be attached to the perinuclear membrane
Rough: Ribosomes
● Double membrane-bound organelle
● Appear as folded layers that seems to be connected to the nuclear membrane
Endoplasmic reticulum
2 types:
○ Rough ER
○ Smooth ER
Endoplasmic reticulum
Responsible for protein synthesis because of the ribosomes embedded in this membrane. This is situated very near the nuclear membrane for the translation to occur.
RER
This double membrane folded in layers is called
in such a way because of the absence of the ribosome in its membrane. This is responsible for glucose and lipid synthesis
SER
● Network of smooth membranes consisting of flattened, disc-like cisternae with dilated rims and associated vesicles and tubules
● Where newly synthesized proteins is processed and modified
Golgi body
● Provides energy to the cell by producing ATPs in a process called cellular respiration
● Contains several enzymes and proteins embedded in its inner membrane called cristae
Mitochondrion
Mitochondria contains several enzymes and proteins embedded in its inner membrane called
Cristae
● A type of Plastid which is found in plant cell
● Contains Chlorophyll located at the Thylakoid membrane
Chloroplast
__________ are stacked together to form Granum (plural Grana) suspended in stroma
Thylakoid
Responsible for the process called photosynthesis
Chloroplast
A complex structure that contains two barrel-shaped centrioles surrounded by amorphous, electron dense pericentriolar material (PCM)
Centromere
● A single membrane-bound organelle
● In animal cells, ________ are generally small and help
sequester waste products
● In plant cell, this is a fluid filled structure that is made up
mostly of water
Vacuole
An elaborate interactive network composed of three well defined filamentous structures – microtubules, microfilaments, and intermediate filaments
Cytoskeleton
Provide structural support and internal framework responsible for positioning various organelles within the interior of the cell
Cytoskeleton
Provides movement of materials and organelles in the cell
Cytoskeleton
A type of cytoskeleton found in the interior of the cell where they maintain cell shape by resisting compressive forces.
Microtubules
A type of cytoskeleton that…
○ Thicken the cortex around the inner edge of a cell
○ They resist tension.
Microfilaments
A type of cytoskeleton…
Found throughout the cell and hold organelles in place
Intermediate filaments
● Also known as microbodies
Peroxisomes
● Membrane bound, multi-functional organelles that carry
out a diverse metabolic reactions including substrate oxidation leading to formation of hydrogen peroxide
Peroxisomes
The command center of the cell because it commands the cellular activity of the entire cell
Nucleus
Nucleus is made up of
○ Nuclear membrane
○ Chromosomes
○ Nucleolus
__________ is made up of two layers of membrane: an outer membrane and an inner membrane
Nuclear envelope or Nuclear membrane
○ Each of these membranes contains two layers of phospholipids, arranged with their tails pointing inward (forming a phospholipid bilayer)
○ It contains nuclear pores for easy transport of materials such as mRNA to the cytoplasm
Nuclear membrane
○ Are threadlike strands of nuclear DNA with proteins called histones
○ These are carrier of genetic materials that occur by pairs (with homologous chromosomes)
○ In mitosis, the chromosomes condensed from chromatin to meta-chromosome becoming more visible under the light microscope
Chromosome
○ Found inside the nucleus suspended in nucleoplasm
○ It is an irregular-shaped nuclear structures that function as ribosome-producing organelle
○ It is more prominent during interphase stage
Nucleolus
● A rigid structure found in plants
● This provides support and protection for the cell it
surrounds
● Contains pectin, glycan and cellulose microfibrils
● Expands from primary cell wall to middle lamella
Cell wall
