Cell Tour Quiz Review

What do both prokaryote and eukaryotes have

cytoplasm, DNA, ribosomes, cell membrane

What do only prokaryotes have

no nucleus, all unicellular, small and simple, binary fission (split in half), no organelles, one small circular chromosome, can use anaerobic and aerobic

What do only eukaryotes have

have nucleus, mostly multicellular, larger and complex, mitosis, organelles, many linear chromosomes, only use aerobic

Cytoplasm

the fluid inside the cell made of water, salts, and various organic molecules

Cytoskeleton

a collection of fibers that will provide support for the cell and its organelles; Provides tracts for materials to move in cell, cell motility, moves chromosomes, anchors organelles, anchors the cell; made of microtubules, microfilaments, intermediate filaments

Microtubules

made of Tubulin; parts of the cytoskeleton that are the tracts, are spindle fibers that move the chromosomes, makes up the cilia and flagella

Microfilaments

made of Actin; anchor the cell/the cell membrane

Intermediate filaments

made of Keratin; anchor the organelles

Ribosomes

make proteins; free and bound ribosomes

Free ribosomes

NOT membrane bound organelles and they are going to be in both prokaryotes and eukaryotes; The proteins made stay inside the cell

Bound ribosomes

attached to the rough ER

Bound ribosome translation process

mRNA initially translated on a ribosome in the cytoplasm; A signal sequence, which is 20 hydrophobic amino acids is recognized by the SRP; SRP directs the ribosome/polypeptide/mRNA complex to a SRP receptor on the rough ER; The ribosome/polypeptide/mRNA is transported to a translocon protein, where translation continues, and the polypeptide chain is threaded into the lumen of the ER.

Nucleus

stores DNA and nucleolus

Nucleolus

produces ribosomes

How is DNA packaged in the nucleus

DNA and histone proteins folds which makes it chromatin which folds again and makes it into chromosomes

Endoplasmic reticulum

attached to the membrane of the nucleus; rough and smooth ER

Rough ER

contains bound ribosomes that produce proteins which leave the cell or go to the lysosome

Smooth ER

Stores calcium, detoxification, and makes lipids

How is it determined if a protein is translated on a free ribosome or a bound ribosome

signal sequence is 20 amino acids that are hydrophobic that if present, the polypeptide chain will be translated on a bound ribosome

Post translational modifications in the rough ER lumen

chaperone folds it and N-linked glycosylation

N-linked glycosylation

sugar is added to the proteins in the lumen to help fold it and make it into a protein

What happens if the protein isn’t folded properly

forms aggregates or sent to the proteosome

Golgi apparatus function

factory in which proteins received from the ER are further processed and sorted for transport to their eventual destinations

Golgi apparatus modifications

modifications to N-linked glycosylation (altering sugar pattern) at the cis end; add O-linked glycosylation at medial; M6-P is added at trans Golgi for proteins destined to the lysosome; proteins secreted out of the cell or the cell membrane don’t have M6-P (happens at trans end)

Lysosome

Has hydrolytic enzymes to break down food, bacteria, damaged organelles; work best at low pH

Mitochondria

Cellular respiration and turning glucose into ATP

Chloroplast

a type of membrane-bound organelle known as a plastid that conducts photosynthesis

Vacuole

Contain water and materials (sugars/salts); Animal has several small ones, plants have one large one

Cell wall

Support/structure and allows the cell to take in a lot of water; plant cell only

Differences between plant and animal cell

Plant cells have chloroplasts, animals have several small vacuoles and plants have one large one, plant cells have a cell wall

Intracellular junction

Allow for exchange of materials between cells (plasmodesmata, gap junction), seal cells together

Plasmodesmata

Only in plant cells; allows for exchange of materials

Gap junction

Only in animal cells; allows for exchange of materials

Tight junction

Seals cells together; only in animal cells

Structure of extracellular matrix

Composed of proteins and glycoproteins (collagen, proteoglycans, fibronectin) that are outside the cell that bind to integral protein outside the cell

Extracellular matrix function

Holds tissue together, cell communication/signaling