understanding living things

Question 1

what are the 7 characteristics of living things?

Answer 1

cells and organisation
energy use and metabolism
response to environmental changes
regulation and homeostasis
reproduction
growth and development
biological evolution

Question 2

describe metabolism

Answer 2

catabolism + anabolism, where catabolism is the breaking down of compounds to generate ATP, and anabolism is the building up of compounds using ATP

Question 3

what is a stimulus

Answer 3

anything that causes a reaction or change in an organism or any part of an organism

there must be the correct receptor for the corresponding stimuli and, the organism is aware and can respond to changes in the environment for its survival

Question 4

what is the road from stimulus to reaction

Answer 4

stimulus (bright) - receptor (sensory cells in eyes) - messenger (nerve) - effector (muscle) - response (muscle contracts)

Question 5

what is homeostasis

Answer 5

regardless of what happens in the external environment, organisms must regulate their cells and body to maintain a stable internal environment (homeostasis)

eg. temperature, ionic and acidic balance

Question 6

what are the types of reproduction

Answer 6

reproduction can be done through asexual (eg. binary fission of bacteria) or sexual reproduction (eg. union fission of sperm and egg to form embryo)

Question 7

what is growth programmed by?

Answer 7

determined by deoxyribonucleic acid

Question 8

what is biological evolution

Answer 8

changes at the genetic level over time where traits are passed down the next generation