Life Science Unit 7-1 Bacteria & Viruses
22 Questions
100 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What are the two types of prokaryotes--bacteria and ___?

archea

A typical bacterium consists of DNA and ___ surrounded by a cell membrane and a cell wall.

cytoplasm

Bacterial cytoplasm also contains ___.

ribosomes

Bacterial DNA occurs in one coiled, circular ___.

<p>chromosome</p> Signup and view all the answers

A bacterium might also have smaller, circular ___ that are separate from its other DNA.

<p>plasmids</p> Signup and view all the answers

Bacteria are much ___________ than plant or animal cells.

<p>smaller</p> Signup and view all the answers

Many bacteria have capsules with hairlike structures called ___.

<p>Pili</p> Signup and view all the answers

Bacteria generally have 1 of 3 basic shapes-- sphere, rod, or ___.

<p>spiral</p> Signup and view all the answers

Some bacteria take in food and break it down and obtain ___.

<p>energy</p> Signup and view all the answers

The food can come from dead organisms or ___ hosts.

<p>living</p> Signup and view all the answers

___ bacteria can survive without oxygen.

<p>Anaerobic</p> Signup and view all the answers

___ bacteria need oxygen, as humans do.

<p>Aerobic</p> Signup and view all the answers

Many bacteria have long whiplike structures called ___ that they use for movement.

<p>flagella</p> Signup and view all the answers

Bacteria reproduce asexually by ___.

<p>fission</p> Signup and view all the answers

During ___, two bacteria of the same species attach to each other and combine their genetic material.

<p>conjugation</p> Signup and view all the answers

___ is transferred between bacteria during conjugation.

<p>DNA</p> Signup and view all the answers

Conjugation results in new combinations of genes and increases genetic ___.

<p>diversity</p> Signup and view all the answers

A ___ forms when a bacterium builds a thick inner wall around its chromosome and part of the cytoplasm.

<p>endospore</p> Signup and view all the answers

An endospore can protect a bacterium from intense heat, cold, or _____. It can remain ____ for months or even centuries.

<p>drought, dormant</p> Signup and view all the answers

Like a bacterium, a(n) ______ has a cell wall but no nucleus or membrane-bound organelles.

<p>Archaean</p> Signup and view all the answers

The ribosomes of archaea more closely resemble the ribosomes of ___ than those of bacteria.

<p>eukaryotes</p> Signup and view all the answers

Archaea often live in ___ environments, such as hot springs and salt lakes.

<p>extreme</p> Signup and view all the answers

Study Notes

Bacteria Overview

  • Prokaryotes include two main types: bacteria and archaea.
  • Bacteria possess DNA and cytoplasm within a cell membrane and cell wall.

Bacterial Structure

  • Typical bacterial cytoplasm contains ribosomes essential for protein synthesis.
  • Bacterial DNA is organized in one coiled, circular chromosome.
  • Some bacteria may have plasmids, which are smaller, circular DNA separate from chromosomal DNA.
  • Bacteria are smaller in size compared to plant and animal cells.

Bacterial Features

  • Many bacteria have pili, which are hairlike structures on their capsules.
  • Bacteria exhibit three basic shapes: spherical (cocci), rod-shaped (bacilli), and spiral (spirilla).

Nutrition and Energy

  • Some bacteria obtain energy by breaking down food sources, which can be derived from dead organisms or living hosts.
  • Aerobic bacteria require oxygen for survival, while anaerobic bacteria can thrive without it.

Movement and Reproduction

  • Bacteria may possess flagella, long whiplike structures used for movement.
  • Asexual reproduction in bacteria occurs through a process called fission.
  • Conjugation allows two bacteria of the same species to connect and transfer genetic material, promoting genetic diversity.

Genetic Transfer and Survival

  • DNA is exchanged during conjugation, leading to new genetic combinations.
  • Endospores form when bacteria create a thick inner wall around their chromosome and part of the cytoplasm.
  • This structural adaptation protects bacteria from extreme temperatures and drought, enabling a dormant state lasting months to centuries.

Archaea Characteristics

  • Archaea share similarities with bacteria, having a cell wall but lacking a nucleus or membrane-bound organelles.
  • The ribosomes of archaea closely resemble those found in eukaryotes rather than bacteria.
  • Archaea thrive in extreme environments, such as hot springs and salt lakes.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

Description

Test your knowledge of bacteria and viruses with this flashcard quiz from Life Science Unit 7-1. Each card presents key terms and concepts essential to understanding prokaryotes, their structures, and functions. Perfect for reviewing before an exam!

More Like This

Use Quizgecko on...
Browser
Browser