MMQ 2 - reflex arcs, resting membrane potential, gametes, prokaryotic cells

Where would you find the coordinating centre for pupil reflex?

Midbrain

Where would you find photoreceptors in the human body?

Retina

In the presence of bright light, __________ muscles in the iris contract and __________ muscles relax.

Circular

Radial

In the presence of dim light, _____________ motor neurones send nerve impulses to ___________ muscles causing them to contract.

Sympathetic

Radial

What is the approximate resting membrane potential?

-70mV

The sodium potassium pump actively transports _____ Na+ ions _____ of the cell and ___ K+ ions ______ the cell.

3 Na+ ions out

2 K+ ions in

Comment on the permeability of the membrane to Na+ ions at rest.

Impermeable

At rest, K+ ions move out of / into (circle one) through potassium ion channels by

___________________________________.

Out of/ into

Facilitated diffusion

What type of Na+ gradient is established by the sodium potassium pump at rest?

Electrochemical

What type of cells lining the oviduct waft the ovum towards the uterus?

Ciliated cells

Cells surrounding the ovum release _____________ which attracts the sperm to it.

Chemicals

What do you call the outer jelly-like coating of the ovum?

Zona pellucida

In which part of a sperm cell would you find digestive enzymes?

Acrosome

When the acrosome swells, what specific structure does the acrosome fuse with?

Cell surface membrane of sperm

What do you call the reaction whereby the outer layer of the ovum thickens to prevent other sperm from entering the egg?

Cortical reaction

Where does respiration happen in a bacteria?

Infolding of cell surface membrane or mesosome

What substance makes up the cell wall of bacteria?

Peptidoglycan

What do you call the thin protein tubes that allow bacteria to adhere to surfaces?

Pili

In what 2 forms does DNA exist in a bacteria?

1. Circular DNA

2. Plasmid

What do you call the slimy layer on the surface of bacteria that is used for protection and to prevent dehydration?

Capsule