4.2.5 Life Science Practice

4.2.5 Cell Nutrition & Transport

- Summarize the processes and changes involved in heterotrophic and autotrophic nutrition in cells.

- Explain how parts of a cell contribute to obtaining nutrients, making needed materials, and removing waste for cells.

- Use a model to explain how cells maintain homeostasis by moving materials across the cell membrane.

Heterotrophs (Other-Feeders)

• Humans and animals - eat plants and other animals

• Bacteria & Fungi - feed on dead and decaying matter

• CANNOT MAKE THEIR OWN FOOD

• Example: Paramecium caudatum - They live in water and use hairlike parts to swim and feed. The "hairs" sweep food into a mouthlike opening

Multiple Select

Which TWO statements represent OTHER-FEEDERS

• A sunflower uses photosynthesis to make its seeds

• Grass takes in energy from sunlight

• A venus flytrap catches and consumes a fly

• A student eats a burger

Multiple Choice

Is this a self-feeder (autotroph) or other-feeder (heterotroph)?

• Self-feeder

• Other-feeder

Autotrophs (Self-Feeders)

• Most plants

• Algae

• Use photosynthesis

Photosynthesis = Food (self-feeders)

• makes organic matter from inorganic substances

• green chloroplasts contain chlorophyll, which captures energy from sunlight

• The energy is used to break apart water (H₂O) molecules

• The oxygen atoms form oxygen (O₂) gas. The hydrogen atoms and carbon dioxide (CO₂) are used to make a sugar. The starch and lipids shown here were made from that sugar.

Multiple Choice

What pigment absorbs sunlight for photosynthesis?

• chloroplast
• thylakoid
• grana
• chlorophyll

Multiple Choice

In what organelle of plant cells does photosynthesis occur?

• mitochondria

• centrioles

• chloroplast

• ribosomes

Cellular Respiration = Energy from food

• the cells of BOTH plants and animals break down food molecules into smaller units. This releases some of the energy stored in the food

• then the mitochondrion use oxygen (O₂) to convert even more food to energy

• Three waste products - carbon dioxide (CO₂), water (H₂O), and thermal energy

Multiple Choice

Cellular respiration occurs in which cell organelle?

• chloroplasts

• mitochondria

• golgi aparatus

• thylakoid

Multiple Choice

Who performs cellular respiration?

• Animals

• Both animals and plants

• plants

Multiple Choice

How do mitochondria get the materials they need?

• They use energy from sunlight to change inorganic matter into organic matter.

• They convert energy stored in organic compounds into a usable form.

• They push particles against their natural direction of flow.

• They provide instructions needed to make proteins from amino acids.

Multiple Choice

Cellular respiration is...

• the process by which cells break down glucose into energy. 
• the process by which cells break light down into energy. 
• the process by which cells communicate with other cells. 

Multiple Choice

The purpose of cellular respiration is to produce ?

• energy

• oxygen

• sugar

• protein

Multiple Choice

Cellular respiration occurs in which cell organelle?

• chloroplasts

• mitochondria

• golgi aparatus

• thylakoid

How we get the food & energy we need

• A self-feeder makes food molecules from inorganic materials

• An other-feeder eats a self-feeder

• Digestion breaks down food molecules

• Cells arrange the organic compounds into the specific molecules they need

By controlling what crosses the membrane, the cell can maintain homeostasis

Passive Transport does NOT require energy

Simple Transport

• Small molecules (CO₂, O₂) easily pass through the membrane

• Molecules pass BETWEEN the PHOSPHOLIPIDS

• Does NOT require extra energy

Moves from HIGH CONCENTRATION to LOW CONCENTRATION

Multiple Choice

How can small oxygen molecules move across cell membranes?

• They merge with the cell membrane to form a vacuole

• They become transport proteins in the cell membrane

• They move to an area with a low concentration of oxygen

• They move to an area with a high concentration of oxygen

Bulk Transport

• Cells take in large food particles and release large chunks of waste

• Requires ENERGY

• The cell membrane surrounds the particle and creates a VACUOLE that enters the cell

Multiple Select

What are the TWO ways that cells get food/nutrients?

• A chloroplast converts energy from sunlight into organic matter.

• Transport proteins help molecules cross cell membranes.

• The nucleus provides the instructions for making proteins from amino acids.

• Mitochondria change energy stored in organic compounds into a usable

  form.

Multiple Choice

How do cells get rid of waste?

• Mitochondria break down glucose to create energy (ATP)

• Vacuoles merge with the cell membrane and then open and/or small molecules pass through the membrane

• The nucleus provides instructions for making proteins