bio practice p2

• Chromosomes are thread-like structures made up of DNA and proteins found inside the nucleus.
• Cell membrane - A thin layer surrounding the cytoplasm that regulates what enters or leaves the cell.
• Ribosome - A tiny structure where protein synthesis occurs.
• Nucleolus - A small structure within the nucleus responsible for producing ribosomes.
• Cytoplasm - The fluid substance within a cell, containing organelles and other substances.
• The human body has two sets of chromosomes, one from each parent.
• Nucleolus - The site within the nucleus where ribosomal RNA is produced.
• Mitochondria - The powerhouse of the cell, converting glucose into energy through aerobic respiration.
• Mitochondria - Organelles responsible for producing energy through respiration.
• Vacuole - A fluid-filled organelle involved in storage, waste disposal, and maintaining turgor pressure.
• Lysosome - An organelle containing enzymes that break down substances.
• Vacuole - A fluid-filled sac that stores water, nutrients, waste products, and pigments.
• Lysosome - An enzyme-filled vesicle that breaks down waste materials and old organelles.
• Human cells have a diploid number of chromosomes (2n = 46).
• Chromatin - DNA wrapped around proteins called histones to form chromosomes.
• Cell membrane - The outer boundary of the cell that regulates what enters or exits the cell.
• Gene expression - Process by which genes are activated or deactivated.
• Ribosome - Small structures found inside cells that are involved in protein synthesis.
• Chloroplast - An organelle found only in plant cells, responsible for photosynthesis.
• Ribosome - An organelle that synthesizes proteins using information from DNA or mRNA.
• Ribosome - Small structures found on the surface or inside cells that synthesize proteins using genetic information from DNA.
• Present Continuous/Present Progressive Tense

  Form: (am/is/are + present participle)
• Present Continuous

  • Use 1: To express that something is happening now, at this very moment
  • Use 2: To express that a longer action is in progress, but not necessarily happening at this exact second
  • Use 3: To indicate that something will or will not happen in the near future
  • Use 4: With words like "always" or "constantly" to express repetition or irritation
• Present Perfect Continuous

  Form: (has/have + past participle)<|>Used to talk about an action that started in the past and continued until recently or continues into the future
• Present Perfect Continuous

  • Use 1: To talk about actions that have just finished, but the speaker is interested in the results
  • Use 2: To talk about actions that started in the past and continue in the present
  • Use 3: To talk about a series of actions
• Time markers

  Often used with: since, for, all week, for days, lately, recently, over the last few months
• Present Continuous/Present Perfect Continuous Exercises

  1. It has been raining all week

  2. He is at the library studying, has been reviewing

  3. Have you been exercising?

  4. We have been waiting

  5. A car alarm is ringing, is driving, has been ringing

  6. His English is really improving, has been watching, has been studying

  7. Are you getting enough sleep, have been sleeping, have been feeling, am currently taking
• Past Continuous Tense

  Form: (was/were + present participle)<|>Describes actions or events in the past that were ongoing at the time of speaking
• Past Continuous

  • Use 1: To describe the background in a story written in the past tense
  • Use 2: To describe an unfinished action that was interrupted by another event or action
  • Use 3: To express a change of mind
  • Use 4: With 'wonder' to make a polite request
• Past Perfect Continuous


  Form: (had been + present participle)<|>Used to show that something started in the past and continued up until another time in the past
• Past Perfect Continuous

  • Use 1: To show the duration of an action before something else in the past
  • Use 2: To show the cause of something in the past
• Past Continuous vs Past Perfect Continuous
• Past Continuous vs Past Perfect Continuous Exercises

  1. We had been sleeping

  2. They had been waiting

  3. We had been looking

  4. I had not been walking

  5. How long had she been learning

  6. I was cooking

  7. Julia was doing

  8. James was repairing

  9. Janet was rehearsing

  10. 10. Sophia was waiting
• Future Continuous


  Form: (will be + present participle)<|>Expresses an ongoing action in the future
• Future Continuous


  • You will be waiting for her when her plane arrives tonight
  • Will you be waiting for her
• Putting verbs into correct form

  1. had been sleeping

  2. had been waiting

  3. had been looking

  4. had not been walking

  5. had she been learning

  6. was cooking

  7. was doing

  8. was repairing

  9. was rehearsing

  10. 10. was waiting
• Future Continuous with "Will"

  will be + present participle
• Future Continuous with "Be Going To"


  am/is/are + going to be + present participle
• Future Continuous Forms


  • Interrupted Action in the Future
  • Specific Time as an Interruption in the Future
  • Parallel Actions in the Future
  • Atmosphere in the Future
• No Future in Time Clauses