Homeostasis

Question 1

name the levels of organization

Answer 1

cells, tissues, organs, organ systems, organism

Question 2

What is the difference between growth and development?

Answer 2

Growth - refers to the number and size of cells

Development - stages where specialized tissues, organs, and organ systems form.

Question 3

What is interstitial fluid and plasma?

Answer 3

fluid between the cells

Question 4

Define homeostasis

Answer 4

When cells, tissues, organs, and organ systems interact to keep internal environment within tolerable limits.

Question 5

What are some challenges organisms face that require homeostasis?

Answer 5

gas exchange, internal transport, water/solute balance, cell-to-cell communication, variations in resources and threats

Question 6

What is the difference between negative and positive feedback loops? Give an example for each.

Answer 6

Negative feedback loops slowly reduce a signal as a target approaches. (ex. regulating temperature). Positive feedback loops intensify a signal until the goal is reached. (labor intensifies towards final birth).

Question 7

What does a plant do to wall-off threats?

Answer 7

toxin release, pathogens, dead-cells (Knotts in wood, compartmentalization).

Question 8

What is apoptosis?

Answer 8

Cell suicide

Question 9

Explain the steps of cell signaling. Give an example.

Answer 9

1. A cell with a receptor protein receives a signal 2. The process of transduction begins, changing the receptor protein (or, the message). 3. This triggers a cellular response. (e.g. apoptosis, or reproduction)