Examkrackers Biology: Lecture 4

Front 1

1) rER
2) Golgi
3) Lysosomes
4) sER

Back 1

1. has ribosomes attached to its cytosol side. It synthesizes virtually all proteins not used in the cytosol. Proteins synthesized on the rER are pushed into the ER lumen and sent to the golgi
2.modifies and packages proteins for use in other parts of the cell and outside the cell
3. contain hydrolytic enzymes that digest substances taken in by endocytosis
4. site of lipid synthesis. Also helps detoxify some drugs

Front 2

Difference between microtubules and microfilaments
-where are cilia found in humans?

Back 2

Microtubules are larger and are involved in flagella and cilia construction and the spindle apparatus. In humans, cilia are found only in the fallopian tubes and the respiratory tract.
Microfilaments squeeze the membrane together in phagocytosis and cytokinesis. They also are the contractile force in microvilli and muscle

Front 3

What is the difference b/t Eukaryotic and Prokaryotic flagella?

Back 3

Eukaryotic flagella has a 9+2 microtubule configuration, while prokaryotes have a single thin strand of protein called flagellin.
Eukaryotic flagella undergo a whip-like action, while prokaryotic flagella rotate

Front 4

Describe the three types of junctions that hold cells together:
1) Tight junctions
2) Desmosomes
3) Gap junctions

Back 4

1. form a watertight seal from cell to cell that can block water, ions, and other molecules from moving around past cells
2. join two cells at a single point
3. small tunnels connecting cells allowing small molecules and ions to move between cells

Front 5

What are the main differences b/t neuronal and hormonal communication?

The neurotransmitter diffuses across the synaptic cleft via brownian motion, which is?

Back 5

Neuronal is fast, direct, and specific while hormonal is slow, spread throughout the body, and affects many cells and tissues in different ways

The random movement of molecules

Front 6

Describe these 3 types of neurons:
1) Sensory (afferent) neurons
2) Interneurons
3) Motor (efferent) neurons

Back 6

1) receive signals from receptor cell that interacts with environment and transfers the signal to other neurons
2) transfers signals from neuron to neuron (90% of neurons in the body are interneurons)
3) carry signals to a muscle or gland

Sensory are located dorsally (toward the back), while motor are located ventrally (toward the front)

Front 7

The cochlea detects _________, while the semicircular canals detect __________.

Back 7

a: sound b: orientation and movement of head