Anthony Albanese’s new ministry will be sworn in with a record number of women on the frontbench.

But the major shakeup has some questioning the shift of more senior MPs, after Tanya Plibersek was stripped of the education and women portfolios and moved to environment and water.

Deputy Labor leader Richard Marles defended the move, saying the environment ministry could not be characterised as a demotion, with the area front and centre of Labor’s priorities.

“It’s one of the most important ministries we have got which has been an enduring passion for Tanya Plibersek,” he told the Nine Network on Wednesday.

“It’s always been a very senior portfolio in government, particularly Labor governments.

“Getting a government which actually has committed to this, dealing with issues such as the Great Barrier Reef, this is an area where there’s a lot of work to be done.”

The prime minister’s 30-member frontbench will be sworn in at a ceremony at Government House on Wednesday, with 13 women appointed to a ministerial role, and 10 of them in the cabinet.

Mr Marles defended not going with a 50-50 gender split in cabinet.

“It’s a significant moment in the nation’s history,” he told the ABC.

“We have women of enormous calibre in the most senior roles who are going to play a critical part in shaping the policy of this government and the character of this government.”

The new minister for aged care and sport Anika Wells, who will sit in the outer ministry, says she will implement Labor’s key promises.

“I’m very conscious that that is our task and we’re on it to do and to start doing as quickly as we possibly can because people are waiting everyday,” she told the ABC.

“We have to deliver what we’ve committed to, which is things like registered nurses on site 24/7. It’s astonishing to me that that doesn’t already happen, so we need to get that happening.”

Mr Albanese unveiled his cabinet on Tuesday night, with a balance of new faces and MPs who served in the previous Labor government.

“This is the largest number of women who have ever served in an Australian cabinet,” Mr Albanese said.

“We have an overflow of talent on our side of the parliament … it’s the most experienced incoming Labor government in our history since federation.”

The swearing in coincides with Labor securing 77 seats in the House of Representatives, after the marginal seat of Gilmore on the NSW south coast was called for incumbent Fiona Phillips.

While some MPs retained their portfolios from when Labor was in opposition, there was a shake up in some key areas.

Mr Marles will double as the new defence minister while education will be held by Jason Clare, and Clare O’Neil will take on home affairs.

Mark Butler will be in charge of health, Tony Burke the minister for employment and the arts, while Chris Bowen will be climate change and energy minister.

Linda Burney becomes the second First Nations person to be appointed Indigenous Australians minister.

She will work alongside Pat Dodson, who was named a special envoy for reconciliation and implementing the Uluru Statement from the Heart.

New faces to the frontbench include Ms Wells, Anne Aly in early childhood and youth, and Kristy McBain in regional development, local government and territories.